Objective:To extract DNA from paraffin-embedded tissue by silica-extraction. Methods:The DNA samples were obtained via silica-extraction method from 49 cases of paraffin-embedded tumor tissues from Department of Pathology in the First Affiliated Hospital of NJMU. The 16 STR gene loci of PCR-DNA fragments were identified with Identifiler Kit. The purity of DNA extracted was analyzed by ultraviolet spectrophotometer. Results:The mean D(260 nm)/D(280 nm) of DNA extracted from gastric carcinoma was 1.84 ± 0.02,from pulmonary carcinoma is 1.85 ± 0.02,from thyroid carcinoma was 1.82 ± 0.02. There was no significant difference in D(260 nm)/D(280 nm) among three carcinoma type groups(P > 0.05). The 46/49 cases(93%) showed the full peaks of all the 16 STR gene loci of PCR-DNA fragment. Conclusion:Silica-extraction may be used to various kinds of paraffin-embedded tissues and extract DNA with high purity and high integrity.