The folk riddle, from oral traditions, is a rapidly disappearing ancient cultural genre, characterized by brevity, eccentricity and poetic intensity. This study is devoted to the reconstruction of the fundamental features of the genre from extant material and formulates the results in the form of a kind of “genetic code”. The generally accepted ideas among folklorists are put to the test and a fresh look at the structure and life of the riddle in their interrelation is formed. The riddle appears as an extremely unique and complex figure of speech and a necessary institution in the life of an ancient and traditional society.