 Albert PréjeanLe commissaire Maigret | Le commissaire Maigret |
 Santa RelliCécile | Cécile |
| GGermaine KerjeanMadame Boynet | Madame Boynet |
 Luce FabioleMadame Petitot, la concierge | Madame Petitot, la concierge |
| LLiliane MaignéNouchi | Nouchi |
 André GabrielloLucas (as Gabriello) | Lucas (as Gabriello) |
 Jean BrochardDandurand | Dandurand |
 Yves DeniaudMachepied | Machepied |
 André ReybazGérard Pardon | Gérard Pardon |
 Marcel CarpentierDr. Pierre | Dr. Pierre |
 Marcel AndréLe directeur de la P.J. | Le directeur de la P.J. |
 Henry BonvalletLe juge d'instruction (as Henri Bonvalet) | Le juge d'instruction (as Henri Bonvalet) |
 Charles BlavetteMonfils | Monfils |
 France AsselinHélène Pardon (uncredited) | Hélène Pardon (uncredited) |
| PPaul BargeMonsieur Louis (uncredited) | Monsieur Louis (uncredited) |
 Jacques BeauvaisMonsieur Paul (uncredited) | Monsieur Paul (uncredited) |
| FFernand BlotUn inspecteur (uncredited) | Un inspecteur (uncredited) |
 Charles CamusLéopold (uncredited) | Léopold (uncredited) |
 Jean ClarieuxVoyageur dans le métro (uncredited) | Voyageur dans le métro (uncredited) |
| MMarius David(uncredited) | (uncredited) |
| CCharlotte EcardL'amie de la concierge (uncredited) | L'amie de la concierge (uncredited) |
 Pierre FervalUn gendarme (uncredited) | Un gendarme (uncredited) |
| EEugène FrouhinsLe serrurier (uncredited) | Le serrurier (uncredited) |
 Gustave GalletLe médecin (uncredited) | Le médecin (uncredited) |
| AAlice GossetLa femme au tandem (uncredited) | La femme au tandem (uncredited) |
 Georges GossetL'homme au tandem (uncredited) | L'homme au tandem (uncredited) |
| CCharles LavialleLe raccommodeur de faïence (uncredited) | Le raccommodeur de faïence (uncredited) |
 Jean MartinLe garçon d'étage (uncredited) | Le garçon d'étage (uncredited) |
 Marcel MelracLe chauffeur de taxi (uncredited) | Le chauffeur de taxi (uncredited) |
 Geneviève MorelUne amie de Madame Petiot (uncredited) | Une amie de Madame Petiot (uncredited) |
