Abstract: Cheng-Zhu's idealist philosophy is a school of thought in the Song-Ming idealist philosophy and is the ruling thought in the latter half of Chinese feu-dal society. The thoughts of criminal psychology is a part of the whole sys-tem of thought,and it is representative and influential in criminal psychologyin ancient China. This article explores the thoughts of criminal psychologyof idealist philosophy in three respects: 1) humanity and crime; 2) desireand crime; and 3) punishment and instruction.

Key words: criminal psychology, humanity, desire, idealist philosophy, punishment instruction