An experiment was carried out in rice field of Krishi Vigyan Kendra (KVK), Kumarakom during 2017 to 2018 to study the influence of rice-fish and rice-water fallow systems on carbon dynamics in Kari soil. The samples were analysed for bulk density, soil pH and soil C pools. Bulk density (BD) of the soil showed no significant difference between rice-fish and rice-water fallow systems.