In order to explore the engineering characteristics of marine silt cement-soil in Xiamen, the mixed proportion of tests of cement-soil is formulated according to the physical and mechanical property indexes of soil. The mechanical parameters of cement-soil were obtained by unconfined compression test and direct shear test, and the influence of water content, age of cement-soil and cement content on the mechanical properties of cement-soil was analyzed. The results show that when the initial water content of marine silt is 45%~65% and the cement content is 9%~21%, the unconfined compressive strength of cement-soil is 0.46~5.38 MPa, the internal friction angle is 13.61°~41.99°, and the cohesion is 65.8~787.25 kPa, the water content of 55% is the dividing line of the influence of cement content on the strength of cement-soil. When the cement content is lower than 18%, the compressive strength and cohesion of cement-soil increase approximately linearly, and the strength growth rate of cement-soil with initial soil water content of 45% is greater than that of 55% and 65%; When the cement content is greater than 18%, the growth rate of strength index decreases. On the basis of the test results, an unconfined compressive strength prediction formula suitable for Marine silt cement soil in Xiamen is put forward.