Abstract: Objective 　To study the effect and mechanism of p27mt gene for the growth inhibition and anti2 metastasis of human colorectal carcinoma t ransplanted in naked mice. Methods 　The model of t ransplan2 ted colorectal Lovo cell line of colorectal carcinoma in naked mice was set up. Ad2p27mt was directly in2 jected into tumor. The t ransplanted tumor size, cell cycle, proliferation index ( PI) and apoptosis rates were observed, MMP29 expression levels were observed also. Results 　The mean volume of Ad2p27mt group, Ad2LacZ group and cont rol group was (1. 94 ±0. 67) cm3 、(2. 75 ±0. 83) cm3 and (3. 01 ±0. 76) cm3 ( P < 0. 05) ;the growth rate was (37. 34 ±1. 45) %、(53. 16 ±3. 27) % and (54. 48 ±2. 43) %( P < 0. 05) ; the apoptosis rate was (19. 79 ±3. 32) %, (6. 38 ±4. 91) % and (7. 25 ±5. 20) %( P < 0. 01) ; The expres2 sion rate of MMP29 was 20 %、75 % and 66. 7 %( P < 0. 01), respectively. Conclusion 　p27mt gene can ob2 viously suppress the growth of t ransplanted colorectal carcinoma. The mechanism dues to inhibit tumor proliferation and promote apoptosis. p27mt gene can suppress metastasis of colorectal cancer in naked mice, the mechanism partially dues to decrease the expression of MMP29.