The relationship among calcite and characteristics of karst, fault zone and ground water are studied, so as to improve the accuracy of geological prediction in construction of karst tunnels. The geological prediction method, which is based on the analysis on the content and characteristics of calcites and the application of geophysical prospecting technology, is proposed. Conclusions drawn are as follows: 1) Anomalous bodies can be detected by means of analyzing the characteristics of calcite, under the help of geophysical prospecting technology. 2) Geological technology and geophysical prospecting technology are needed in geological prediction so as to achieve accurate prediction results. 3) With the help of statistics of and studying on micro phenomenon, macroscopical structures can be detected.