Microbial geotechnical technology is to improve the mechanical properties of basic materials through the process of biological mineralization, so that it is more suitable for building or solving environmental problems in multi-disciplinary fields. Calcium carbonate produced in the process of microbial mineralization is the main component to improve the mechanical properties of basic materials, but its production amount and form are affected by many factors. Therefore, the influence of factors such as ion concentration, proportion and bacterio-colloid ratio on the morphology and crystal composition of precipitated materials in the mineralization process of natural seawater and deionized water environment was explored. The results showed that: Calcium ion and urea concentration and proportion is low, the yield of calcium carbonate, but when the initial calcium ion, urea concentration exceeds 1.0 mol/L, ion concentration increase has inhibitory effect to the bacteria to produce urease, the higher the concentration of urea enzyme inhibition, the more obvious, precipitation product rate is reduced, the overall precipitation amount and precipitation rate of the water environment were higher than in deionized water transferred. When the volume ratio of bacterial cementation liquid in deionized water is 1:4 and that in seawater is not higher than 1:10, the amount of calcium carbonate is higher, and the crystal type in deionized water is mainly calcite, while the crystal type in seawater is mainly spherical aragonite, and the precipitation contains magnesium salt.