The present invention is a crystal body configured with a crystal and having a pair of light passing surfaces which face each other and pass light and at least one side surface which connects the pair of the light passing surfaces. In the crystal body according to the present invention, a ratio B/A of a dislocation density A (number/cm2) in the light passing surfaces and a dislocation density B (number/cm2) in the side surface satisfies the following general formula. 1≦(B/A)≦3600  (1)