Microbially induced calcium carbonate precipitation (MICP) technology has broad application value and potential in improving the mechanical properties of rock and soil. However, this method still has defects, such as low efficiency and long reinforcement periods. An appropriate amount of sodium silicate was added to the bacterial solution to enhance the efficiency of MICP reinforcement and shorten the reinforcement period based on conventional MICP. The solution tests and sand column tests were carried out, as well as the macro and micro detection tests. The enhancement effect and mechanism of sodium silicate on microbial sand fixation were studied. The results show that the bacterial activity increased by about 14 % and the amount of calcium carbonate in the sand column increased by about 7 % after adding appropriate amount of sodium silicate, and the MICP reinforcement efficiency and sample uniformity were enhanced. After 2 times of sand column reinforcement, the sample can be formed. After 10 times of reinforcement, the compressive strength of the sample is about 5.9 MPa, which is about seven times higher than that of the control group. Microscopic detection tests show that after adding sodium silicate, the hydrated calcium silicate gel generated in the environment can play a role in filling sand pores and cemented sand particles, thereby improving the strength and reinforcement efficiency of the sample. This method can provide theoretical guidance for popularising and applying microbial sand fixation.