Objective:To study the association of TGF?2 polymorphisms and maternal smoking with the occurrence of nonsyndromic cleft lip and palate(NSCLP). Methods:TGF?2 genes were amplified from peripheral leukocytes by means of PCR in 272 cases of nonsyndromic cleft lip with or without palate(CL/P), 251 of cleft palate only(CPO) and 312 of unrelated controls in Jilin Province, PCR products were analyzed by single-stranded conformation polymorphism(SSCP) and DNA sequencing. Maternal smoking was investigated. The association of TGF?2 polymorphisms, maternal smoking with the occurrence of CL/P and CPO was analyzed by SAS statistic system. Results:The 322 bp PCR product of TGF?2 was amplified from CL/P, CPO and control samples; SSCP analysis showed three alleles of TGF?2;sequencing results showed that allele1, allele2 and allele3 contained seven, eight and nine ACA repeats respectively. The statistic analysis showed that TGF?2 polymorphisms or maternal smoking was associated with the occurrence of CL/P and CPO respectively(P0.05).Conclusion:TGF?2 polymorphisms and maternal smoking during pregnancy are associated with the occurrence of CL/P and CPO. TGF?2 polymorphisms have no interaction with maternal smoking.