Abstract: The gonadosomatic index of the channa marulius from Son river Shahdol. Studies have been carried out the scientific management for obtaining high yield of fish production eventually calls the adequate and in-depth study of breeding mechanism. In order to complete the task present study was undertaken to trace accurately spawning period of channa marulius. This is reported in terms of gonad somatic index which express the relative change in gonad weight to the percentage of body weight. During present study the peak value of GSI was observed only once in the month of May (47.56%) indicating only one spawning period in channa marulius . i.e. from June to August.