T.S. in the New York Times (March 5, 1943):

If "Reunion in France" is the best tribute that Hollywood can muster to the French underground forces of liberation, then let us try another time. For the new film which opened yesterday at the Capitol is again making the shallowest drama out of the pith and substance of an ironic tragedy. It is not a picture of France as it fights today in ways devious and dark; it is more simply a stale melodramatic exercise for a very popular star. In the role of a spoiled rich woman who finds her "soul" in the defeat of France, Joan Crawford is adequate to the story provided her, but that is hardly adequate to the theme. The picture is by MGM, Miss Crawford's ensembles by Irene.

The plot moves by rote, the characters by the most trivial compulsions. Miss Crawford appears as a giddy lady who thinks wars are merely the pastimes of overgrown boys until France is crushed and she returns to Paris to discover that her fiancé, an industrial designer, and the Nazi officials are thick as thieves. Amid her bewilderment she takes a passing fancy to a pursued American flyer, helps him to safety, but returns to her earlier love when she discovers that the designer's vast plants are actually turning out faulty weapons for the Nazis, while simultaneously organizing a nucleus of armed forces for the future.

On the basis of evidence to date, MGM seems somewhat off base when it infers that the initiative for a French resurrection comes from its moneyed society folk and spendthrifts; hardly an ordinary French citizen appears in the film. Instead, most of the action takes place against a background of palatial homes and lavish coutouriere's establishments. Most of the lines and situations might be taken from Italian opera—they're hollow and stilted like the dressmaker's declaration: "How can you expect a woman to cry at the collapse of an empire?"

Under the circumstances, one can't ask too much of the performances. Miss Crawford as usual makes an elegant manikin for a series of ensembles that probably will excite more female comment than the picture itself. Philip Dorn is a good deal better than his role of the designer and John Wayne is totally unconvincing as the American flyer. Lesser roles are played by Albert Basserman, John Carradine and Reginald Owen. As for "Reunion in France," it has had the temerity to be glibly untruthful on serious matters. It has slipped on its own banana oil.

Joseph Pihodna in the New York Herald Tribune (1942):

    Suffice to say that Miss Crawford appears in enough new dresses to please producers and the feminine audience. With all the evidence in, Miss Crawford, as Michele de la Becque, isn't making all the sacrifices implied in the script. She has certain prerogatives. Dressing like a refugee is certainly not in her contract.

tvguide.com:

    Essentially a Crawford vehicle with Wayne in a thankless supporting role, Reunion in France suffers from MGM's desire to turn a serious and volatile subject into a mindless backlot entertainment. Nowhere is this more evident than in the decision to pay more attention to Crawford's dazzling wardrobe than to historical accuracy. Reunion in France will suffice as entertainment if you're prepared to shut your mind off for 104 minutes, but don't expect much more than fluff.

Monsterhunter.com (2004):

    A terrible, unbelievable story that makes little sense on any level and is topped off by the fact that you don't believe anything the stars do in this movie (except for when Duke slugs that Nazi). While Crawford and Wayne might have been perfect for one of those mismatched buddy movies (a la Turner & Hooch), they generate nothing other than to show us what would have happened to Casablanca if it had been hampered by a dull as dirt story (both in smarts, action, and emotion) and stars that thought mouthing bogus platitudes saluting the courage of a people who rolled over like they were the New Jersey Nets or something was somehow inspiring a multitude of people to keep fighting the good fight (or in the French case, to start fighting). ...Sit through this abominable entry in the "Rah, Rah, Rah! Go Allies!" film genre and you understand what they're talking about when you hear people say "war is hell!" Complete--rambling and hilarious--review.