Abstract： Objective To observe the therapeutic effects of pioglitazone combined with insulin on patients with newly diagnosed latent autoimmune diabetes in adult(LADA).Methods All 36 LADA patients were randomly divided into insulin group ( 17 cases) and pioglitazone plus insulin group ( 19 cases).Seventeen patients in insulin group were treated with insulin and 19 patients in pioglitazone plus insulin group were treated with insulin and pioglitazone during twelve months.The changes of fasting plasma glucose (FPG),2-hour plasma glucose (2hPG),glycolated hemoglobin (HbA1c),insulin resistance index (Homa-IRI),body weight,insulin dosage and hypoglycemia events in different groups were compared after treatment for twelve months.Results Compared to pre-treatment,the levels of FPG,2 hPG,and HbA1 c in pioglitazone plus insulin group [ ( 6.4 ± 1.2 ) mmol/L vs (9.1 ± 1.1 )mmol/L,(8.7 ± 2.2) mmol/L vs ( 19.2 ± 2.4) mmol/L,(5.8 ± 1.1 ) ％ vs (8.4 ± 1.3 ) ％ ] and in insulin group [ (6.9 ± 1.2)mmol/L vs (8.4 ± 1.2)mmol/L,(9.0 ± 1.6)mmol/L vs (18.1 ±2.6)mmol/L,(7.2 ± 1.2)％ vs (8.2 ± 1.4) ％ ] after treatment for 12 months were lower( all P ＜0.05).The levels of Homa-IRI,HbA1c,insulin dosage and hypoglycemia events in pioglitazone plus insulin group were lower than those in insulin group [ (5.8 ±1.1)％ vs (7.2 ± 1.1)％,1.16 ±0.25 vs 1.45 ±0.28,(17 ±4)U/d vs (27 ±8)U/d,(0.8 ±0.3)times vs (1.6±0.8)times] (P ＜0.05),while the difference of body weight between the two group had no statistical significance ( P ＞ 0.05).Conclusion The method of pioglitazone combined with insulin treatment can more effectively control blood sugar,reduce the dosage of the insulin and hypoglycemia events and improve insulin resistance in newly diagnosed LADA patients.