Abstract: To improve the quality of the coastal solonchak, effects of both the jute straw and organic fertilizer on both the enzyme activity and microbial number in the coastal saline soil modified with the different level of both the jute straw and organic fertilizer were investigated. The results indicated that: the soil biological properties were obviously ameliorated when the jute straw was applied at the level of 3 600 kg/hm2 and organic fertilizer at the level of 2 400, 3 600 kg/hm2. Compared with the control, the urease activity was increased by 53 % and 98 %, invertase activity by 700 % and 825 %, hydrogen peroxidase activity by 49 % and 65 %, phosphatase activity by 99 % and 161 %, microbial number was increased by a factor of 6.8 and 10.5, fungi amount by a factor of 56.1 and 91.8, namely, relatively large increase amplitude. It is concluded that the application of jute straw and organic fertilizer obviously increased those enzymes activities and microbial number, enhanced soil biological activity, and improved soil fertility.