Le Coup de Lune ([lə ku də lyn]; literally "moonburn" or "moonstroke" in French, but translated into English as Tropic Moon, is a 1933 novel by Belgian writer Georges Simenon.

In his introduction to the New York Review Books edition, Norman Rush finds certain parallels between this work and Journey to the End of the Night by Céline.

The story concerns Joseph Timar, a sensitive young Frenchman, who travels from La Rochelle to Libreville in Gabon to work at a job his uncle has arranged for him at SACOVA, a logging business.

Back in Libreville, still weak and intermittently incoherent, Timar learns that a village man is to be charged with the servant Thomas's murder on the basis of eye-witness accounts.

There are two English translations of Coup de Lune, the first by Stuart Gilbert, which has been included in two anthologies: In Two Latitudes (George Routledge, 1942; Penguin Books, 1952) and African Trio (Harcourt Brace Jovanovich, 1979).