Abstract: Objective To study the association of transfouning growth factor alpha (TGF-α)gene polymoiphisn and folic acid supplementation in Han nationality with nonsyndrom is cleft lip with or without cleft palate (NSCL/P).Methods Data related to folic acid supplementation during the periconceptional period were gained through investigation of patients' mothers Polymerase chain reaction combined with restrictenzyma digestion was used to detect the target gene variation in 199 patients with NSCL/P and 203 healthy controls.Analysis was carried on the genotype and folic acid supplementation.Results The C2 allele frequency in patients with NSCL/P was significantly higher than that of in healthy controll There was a significant increase of NSCL/P in infants with the mothers without folic acid supplem entation during the pregnatncy.There was an interaction between C1C2 genetype and folic acid supplem entation.Conclusion TGF-α gene polymoiphism is closely associated with NSCL/R Folic acid supplem entation during the periconceptional period is associated with the occurrence of NSCL/P.Individuals containing C2 allele are more sensitive to folic acid deficiency.