Abstract：To introduce the clinical experience of Prof. YIN Jianping in treating chronic constipation by syndrome differentiation based on the theory of diseases caused by latent constraints. Starting from the mechanism that the latent pathogen is hidden in the six constraints， including qi， dampness， heat， stasis， blood and food， Prof. YIN focuses on the pathogenic characteristics of failure to transmit by intestine of chronic constipation， and adopts the treatment methods of regulating the middle energizer， diffusing the upper energizer and unblocking the lower energizer. In syndrome differentiation and treatment， Prof. YIN tends to use qi medicinal， follow the three considerations of time， person and place，and adopt prescriptions and medication in a flexible way.