Abstract: Objective To study the expression and correlation of DNA methyltransferase 1（DNMT1）and p27 protein in primary and secondary glioblastoma multiforme. Methods From Jan 1 2000 to Jan 31 2012， 32 cases of primary glioblastoma multiforme specimens， 32 cases of secondary glioblastoma multiforme specimens and 13 cases of normal brain tissues were enrolled. The expression of DNMT1 and p27 protein was detected in those tissues. Results The positive expression rates of DNMT1 protein in primary and secondary glioblastoma multiforme tissues， as well as in normal tissues were 59.4%，81.3% and 0. The positive expression rates of p27 protein were 50.0%，25.0% and 100.0% in primary and secondary glioblastoma multiforme tissues， and normal brain tissues （P<0.05）. The positive expression of DNMT1 and p27 protein in primary and secondary glioblastoma multiforme tissues had significant difference （P<0.05）. There was no correlation between the expressions of both proteins（r=041，P>0.05）. Conclusion The expression of DNMT1 and p27 protein is different in primary and secondary glioblastoma multiforme tissues. The combined detection of DNMT1 and p27 protein may serve as an index to estimate different types of glioblastoma multiforme.