"The Heart of the Serpent" (originally in Latin: Cor Serpentis, Russian: Сердце Змеи) is a 1958 science fiction short story by the Soviet writer and paleontologist Ivan Yefremov.

Comparisons are made to American SF writer Murray Leinster's story "First Contact", in which an elaborate protocol is developed to prevent the aliens from following the Terrans home and destroying them, or vice versa.

The premise of Leinster's story is rejected, in part by pointing out that in order for a planet's civilization to become space-faring, they would need to be at peace among themselves and presumably have organized themselves into a planet-wide classless communist society, a point Yefremov had made earlier in his novel Andromeda.

This story takes place within the rubric of Yefremov's Great Circle, a confederation of galactic civilizations that communicate between each other, which also appears in the Andromeda novel.

The Hungarian space rock band Solaris has a track named after the story on their album 1990.