thumb|De winnende auto: de Renault Alpine A442B #2. De 24 uur van Le Mans 1978 was de 46e editie van deze endurancerace. De race werd verreden op 10 en 11 juni 1978 op het Circuit de la Sarthe nabij Le Mans, Frankrijk.

De race werd gewonnen door de Renault Sport #2 van Didier Pironi en Jean-Pierre Jaussaud. Zij behaalden allebei hun eerste Le Mans-zege. De IMSA GT-klasse werd gewonnen door de Dick Barbour Racing #90 van Dick Barbour, Brian Redman en John Paul sr. De Gr.5 SP-klasse werd gewonnen door de Porsche Kremer Racing #44 van Jim Busby, Chris Cord en Rick Knoop. De GTP-klasse werd gewonnen door de Jean Rondeau #72 van Jean Rondeau, Bernard Darniche en Jacky Haran. De Gr.6 S 2.0-klasse werd gewonnen door de Société Racing Organisation Course La Pierre du Nord #31 van Michel Pignard, Lucien Roussiaud en Laurent Ferrier. De Gr.4 GT-klasse werd gewonnen door de Anne-Charlotte Verney #66 van Anne-Charlotte Verney, Xavier Lapeyre en François Servanin.

Race Winnaars in hun klasse zijn vetgedrukt. Auto's die minder dan 70% van de afstand van de winnaar (258 ronden) hadden afgelegd werden niet geklasseerd. De #12 Simon Phillips Racing en de #33 Cloud Engineering werden gediskwalificeerd omdat zij te veel achterstand hadden opgelopen.

Pos. Klasse No. Team Coureurs Chassis Motor Banden Ronden 1 Gr.6 S 3.0 2 Renault Sport Didier Pironi Jean-Pierre Jaussaud Renault Alpine A442B Renault 2.0L V6 twin-turbo 369 2 Gr.6 S 3.0 6 Martini Racing Porsche System Jürgen Barth Bob Wollek Jacky Ickx Porsche 936-78 Porsche 935/73 2.1L F6 twin-turbo 364 3 Gr.6 S 3.0 7 Martini Racing Porsche System Hurley Haywood Peter Gregg Reinhold Joest Porsche 936-77 Porsche 911/78 2.1L F6 turbo 362 4 Gr.6 S 3.0 4 Renault Sport/Écurie Calberson Guy Fréquelin Jean Ragnotti José Dolhem Jean-Pierre Jabouille Renault-Alpine A442A Renault 2.0L V6 twin-turbo 358 5 IMSA GT 90 Dick Barbour Racing Dick Barbour Brian Redman John Paul sr. Porsche 935-77 Porsche 930/78 3.0L F6 turbo 337 6 Gr.5 SP 44 Porsche Kremer Racing Jim Busby Chris Cord Rick Knoop Porsche 935-77 Porsche 930/72 3.0L F6 turbo 336 7 Gr.5 SP 41 ASA Cachia Team Pace Alfredo Guaraná Paulo Gomes Mário Amaral Porsche 935-77 Porsche 3.0L F6 turbo 329 8 Gr.5 SP 43 Martini Racing Porsche System Rolf Stommelen Manfred Schurti Porsche 935-78 Porsche 935/79 3.2L F6 twin-turbo 326 9 GTP 72 Jean Rondeau Jean Rondeau Bernard Darniche Jacky Haran Rondeau M378 Cosworth DFV 3.0L V8 294 10 Gr.6 S 3.0 10 Grand Touring Cars Inc Vern Schuppan Jacques Laffite Sam Posey Mirage M9 Renault 2.0L V6 turbo 293 11 Gr.6 S 2.0 31 Société Racing Organisation Course La Pierre du Nord Michel Pignard Lucien Roussiaud Laurent Ferrier Chevron B36 Simca-ROC 2.0L S4 284 12 Gr.4 GT 66 Anne-Charlotte Verney/BP Racing Anne-Charlotte Verney Xavier Lapeyre François Servanin Porsche 911 Carrera RSR Porsche 3.0L F6 279 13 GTP 71 André Chevalley Racing André Chevalley François Trisconi Inaltéra LM77 Cosworth DFV 3.0L V8 279 14 IMSA GTX 97 Charles Ivey Racing Larry Perkins Gordon Spice John Rulon-Miller Porsche 911 Carrera RS Porsche 3.0L F6 278 15 Gr.6 S 3.0 8 Alain de Cadenet Alain de Cadenet Chris Craft De Cadenet LM78 Cosworth DFV 3.0L V8 273 16 IMSA GTX 86 Écurie Grand Competition Cars North American Racing Team François Migault Lucien Guitteny Ferrari 365 GT/4 BB Ferrari 4.9L F12 262 17 Gr.4 GT 62 "Ségolen" André Gahinet Christian Bussi Jean-Claude Briavoine Porsche 934 Porsche 3.0L F6 turbo 259 NC Gr.6 S 2.0 23 P. Sauber AG/Francy Racing Marc Surer Eugen Strähl Harry Blumer Sauber C5 BMW-Mader 2.0L S4 257 NC Gr.6 S 2.0 20 Cheetah Racing Cars Sandro Plastina Mario Luini Jean-Daniel Grandjean Cheetah G-601 Cosworth BDG 2.0L S4 250 NC Gr.4 GT 64 Georges Bourdillat Georges Bourdillat Alain-Michel Bernhard Jean-Luc Favresse Porsche 911 Carrera RSR Porsche 3.0L F6 241 NC Gr.6 S 2.0 25 Team Pronuptia Bruno Sotty Gérard Cuynet Jean-Claude Dufrey Lola T294/296 Cosworth FVC 1.9L S4 238 NC Gr.6 S 2.0 24 Team Pronuptia Michel Elkoubi Pierre Yver Philippe Streiff Lola T296 Cosworth FVC 1.9L S4 232 NC Gr.6 S 2.0 28 Dominique Lacaud Dominique Lacaud Michel Lateste Jean-François Auboiron Lola T297 BMW 2.0L S4 217 NC Gr.5 SP 45 Porsche Kremer Racing Louis Krages Dieter Schornstein Philippe Gurdjian Porsche 935-77 Porsche 3.0L F6 turbo 182 DNF Gr.6 S 3.0 1 Renault Sport Jean-Pierre Jabouille Patrick Depailler Renault Alpine A443 Renault 2.1L V6 turbo 279 DNF Gr.6 S 3.0 5 Martini Racing Porsche System Jacky Ickx Henri Pescarolo Jochen Mass Porsche 936-78 Porsche 935/73 2.1LF6 twin-turbo 255 DNF IMSA GTX 88 Pozzi Thompson JMS Racing Jean-Claude Andruet Spartaco Dini Ferrari 512 BB Ferrari 4.9L F12 251 DNF IMSA GTX 87 Luigi Chinetti Sr. Jacques Guérin Jean-Pierre Delaunay Gregg Young Ferrari 512 BB Ferrari 4.9L F12 232 DNF IMSA GTX 89 Pozzi Thompson JMS Racing Claude Ballot-Léna Jean-Louis Lafosse Ferrari 512 BB Ferrari 4.9L F12 218 DNF Gr.6 S 3.0 19 IBEC Racing Developments Guy Edwards Ian Grob Ian Bracey Ibec-Hesketh 308LM Cosworth DFV 3.0L V8 195 DNF Gr.6 S 2.0 30 Société Racing Organisation Course La Pierre du Nord Jacques Henry Albert Dufrène Max Cohen-Olivar Chevron B36 Simca-ROC 2.0L S4 195 DNF GTP 78 WM AEREM/Team Esso Aseptogyl Xavier Mathiot Marc Sourd Christian Debias WM P78 Peugeot PRV 2.7L V6 turbo 186 DNF Gr.6 S 2.0 27 Mogil Motors Ltd/Kores Racing Tony Charnell Robin Smith Fréderic Alliot Richard Jones Chevron B31 Cosworth BDG 2.0L S4 181 DNF GTP 76 WM AEREM/Team Esso Aseptogyl Christine Dacremont Marianne Hoepfner WM P76 Peugeot PRV 2.9L V6 171 DNF Gr.4 GT 68 Hervé Poulain Hervé Poulain Edgar Dören Gerhard Holup Roman Feitler Porsche 934 Porsche 3.0L F6 turbo 167 DNF Gr.6 S 3.0 3 Renault Sport Derek Bell Jean-Pierre Jarier Renault-Alpine A442A Renault 2.0L V6 twin-turbo 162 DNF IMSA GTX 91 Dick Barbour Racing Bob Garretson Steve Earle Bob Akin Porsche 935-77 Porsche 3.0L F6 turbo 159 DNF Gr.6 S 2.0 29 Société Racing Organisation Course/Modylook Michel Dubois Daniel Gache Julien Sanchez Chevron B36 Simca-ROC 2.0L S4 142 DNF Gr.5 SP 48 Mecarillos-Cégécol Racing Team Herbert Müller Claude Haldi Nick McGranger Porsche 935 Porsche 3.0L F6 turbo 140 DNF Gr.6 S 2.0 26 GVEA Georges Morand Eric Vaugnat Christian Blanc Lola T296 Cosworth BDG 2.0L S4 130 DNF Gr.6 S 2.0 21 Jean-Marie Lemerle Jean-Marie Lemerle Alain Levié Pierre-François Rousselot Lola T294 Simca-ROC 2.0L S4 126 DNF Gr.4 GT 65 Joël Laplacette Joël Laplacette Yves Courage Antoine Salamin Gérard Vial Porsche 930 Porsche 3.3L F6 turbo 116 DNF Gr.6 S 2.0 34 BMW (GB) Racing Toleman Delivery Dieter Quester Tom Walkinshaw Rad Dougall Osella PA6 BMW M12 2.0L S4 113 DSQ Gr.6 S 3.0 12 Simon Phillips Racing Simon Phillips Nick Faure John Beasley Martin Raymond De Cadenet-Lola T380 Cosworth DFV 3.0L V8 99 DNF Gr.6 S 2.0 32 Dorset Racing Associates Ian Harrower Juliette Slaughter Brian Joscelyne Lola T294 Cosworth FVC 2.0L S4 61 DNF Gr.4 GT 61 Auto Daniel Urcun Guy Chasseuil Jean-Claude Lefévre Porsche 934 Porsche 3.0L F6 turbo 61 DNF GTP 77 WM AEREM/Team Esso Aseptogyl Jean-Daniel Raulet Max Mamers WM P77 Peugeot PRV 2.7L V6 turbo 44 DNF Gr.5 SP 94 Whittington Bros. Racing Don Whittington Bill Whittington Franz Konrad Porsche 935-77 Porsche 3.0L F6 turbo 41 DNF IMSA GTX 85 "Beurlys" Jean Blaton Teddy Pilette Raymond Touroul Ferrari 512 BB Ferrari 4.9L F12 39 DNF Gr.4 GT 69 Frères Ravenel VSD Willy Braillard Jean-Louis Ravenel Jean Ravenel Porsche 934 Porsche 3.0L F6 turbo 35 DNF Gr.5 SP 46 Porsche Kremer Racing Martin Raymond Jean-Pierre Wielemans Mike Franey Porsche 935-77 Porsche 3.0L F6 turbo 34 DNF Gr.6 S 3.0 11 Grand Touring Cars Sam Posey Michel Leclère Mirage M9 Renault 2.0L V6 turbo 33 DNF IMSA GTX 84 Brad Frisselle Racing Wynn's Belgium Brad Frisselle Bob Kirby John Hotchkis Chevrolet Monza Chevrolet 5.7L V8 30 DSQ Gr.6 S 2.0 33 Cloud Engineering Dorset Racing Associates Bob Evans Richard Down Lola T294 Cosworth FVC 2.0L S4 23 DNF Gr.5 SP 47 Weisberg Gelo Team John Fitzpatrick Toine Hezemans Porsche 935-77 Porsche 3.0L F6 turbo 19 DNQ Gr.6 S 3.0 9 Alain de Cadenet Bob Evans John Cooper Pete Lovett De Cadenet-Lola LM77 Cosworth DFV 3.0L V8 0 DNQ Gr.6 S 3.0 14 BP Racing Jörg Obermoser Guy Chasseuil Hubert Striebig ToJ SC303 Cosworth DFV 3.0L V8 0 DNQ Gr.6 S 2.0 22 L'Agence Locomotiv Anna Cambiaghi Jean-Claude Guérie Martine Rénier Lola T296/297 Simca-ROC 2.0L S4 0 DNQ Gr.5 SP 40 AMG Motorenbau GmbH Hans Heyer Clemens Schickentanz Mercedes-Benz 450 SLC Mercedes-Benz 4.5L V8 0 DNQ Gr.4 GT 60 Mecarillos Racing Team Gérard Bleynie Roland Ennequin Simon Delatour Porsche 934 Porsche 3.0L F6 turbo 0 DNQ Gr.4 GT 63 Christian Gouttepifre Christian Gouttepifre René Boubet Raymond Touroul Porsche 911 Carrera RS Porsche 3.0L F6 0 DNQ Gr.4 GT 73 B. Decure Marcel Mignot Guy de Saintpierre Alpine A310 Renault PRV 2.7L V6 0 DNQ IMSA GT 96 Garage du Bac Alain Cudini Pierre Dieudonné Jean-Claude Depince BMW 3.5 CSL BMW M30 3.5L S6 0 DNQ IMSA GT 98 Thierry Perrier Thierry Perrier Joël Mouetron Jean Belliard Porsche 911 Carrera RS Porsche 3.0L F6 0 DNA Gr.5 SP 42 Konrad Racing Franz Konrad Volkert Merl Porsche 935-77 Porsche 3.0L F6 turbo 0 DNA Gr.5 SP 50 Morfe Racing with Polaroof Richard Jenvey John Morrison Lotus Esprit S1 Lotus 907 2.0L S4 0 DNA GTP 70 Robin Hamilton Robin Hamilton David Preece Aston Martin DBS Aston Martin 5.3L V8 turbo 0 DNA IMSA GT 92 Holly Cars LSA Porsche 934 Porsche 3.0L F6 turbo 0

1978 Le Mans