Abstract: Objective To assess the reliability and validity of SF-12 among floating population.Methods The reliability of the SF-12 was assessed by internal consistency reliability and the validity of SF-12 was evaluated by discriminate validity,convergent validity and structural validity.Results The internal consistency reliability Cronbach's was 0.84.The correlation coefficients between each dmiension and total grade were more than 0.50 except physical functioning (0.43).The Cronbach indexes of all dimensions were more than 0.0,and the Cronbach indexes after de-leting corresponding dmiension were more than 0.70.Convergent validity expermient rate and discrmiinate validity expermient rate were 100%.There sults of confirmatory factor analysis showed that the structure of the constructed model was in accord with the theoretical as sumption with a non-normed fitindex (NNFI) of 0.95,a comparative fit index (CFI) of 0.96,an adjusted goodness of fit index (AGFI) of 0.96,and root mean square error of approxmiation(RMSEA) of 0.06.Conclusion The SF-12 for life quality evaluation among floating population has good reliability and validity.