Objective To investigate the insulin resistance and the changes of pancreaticβ-cell function in order to improve the clinical diagnosis and therapy .Methods 99 cases of pregnant women in the late ministers were randomly selected for the study and divided into three groups(normal glucose tolerance group ,impaired glucose tolerance group ,and gestational diabetes group) .The in-sulin resistance and isletβ-cell function of the three groups were evaluated by HOMA model and its related indicators .Results The blood pressure and blood lipid level was not significant different among the three groups(P>0 .05) .Pairwise comparisons of glu-cose infusion rate ,the first phase insulin secretion ,the second phase insulin secretion ,fasting glucose ,fasting insulin ,HOM A-IR , and HOMA-βwere made among the three groups ,and there were difference with statistical significance(P<0 .05) .Conclusion The situation of insulin resistance and the dysfunction of pancreaticβ-cell in trimester pregnant women would become bad associated with the abnormal glucose tolerance .