【Objective】 To study the yielding rate and distribution of unexpected antibodies in blood transfusion children with thalassemia in Yunnan province, and to explore the blood transfusion strategies. 【Methods】 From January 2016 to December 2021, 298 children with thalassemia, who received blood transfusion treatment in Kunming, Xishuangbanna, Wenshan, Dehong, Yuxi and Baoshan hospitals across Yunnan Province, were selected. The unexpected antibodies of blood plasma were screened by microcolumn gel card. The samples with positive antibodies were identified for alloantibody specificity. 【Results】 Unexpected antibodies were yielded in 67 out of 298(22.48%) transfused children with thalassemia. The positive rates of unexpected antibodies in boys and girls were 16.55%(24/145) and 28.10%(43/153), respectively. The positive rates of unexpected antibodies in Han, Dai, Zhuang, Yi, Bulang, Jinuo and Miao people were 14.06%(18/128), 30.80%(32/104), 35.71%(10/28), 36.36%(8/22), 50.00%(4/8), 60.00%(3/5)and 66.67%(2/3), respectively, with statistically significant differences between each other. The positive rate of unexpected antibodies in ethnic minorities was higher than that in Han. The positive rates of unexpected antibodies in children who received the first transfusion at birth-one year old, 1~3 years old, 3~6 years old and above 6 years old were 12.50%(3/24), 10.14%(7/69), 24.54%(40/163)and 40.48%(17/42), respectively. The positive rates of unexpected antibodies in children with first transfusion after 3 years old were significantly higher than those before 3 years old. The positive rates of unexpected antibodies in children with one transfusion, 1~3, 3~10, 10~20 and more than 20 transfusions were 4.76%(1/21), 12.07%(7/58), 23.71%(23/97), 28.16%(29/103)and 36.84%(7/19), respectively, with statistically significant differences between each other. The number of blood transfusions was positively correlated with the unexpected antibody yielding. The yielding rate of unexpected antibodies in children with α thalassemia, βthalassemia, δ+ βthalassemia and untyped thalassemia was 7.50%(3/40), 17.62%(34/193), 53.70%(29/54)and 9.09%(1/11), respectively(P<0.05). The yielding rate of unexpected antibodies in transfused children with δ+ βthalassemia was the highest. And 57 unexpected antibodies of Rh blood group system were yielded, 6 anti-M antibodies, 2 anti-N antibodies and 2 undetermined. 【Conclusion】 The positive rate of unexpected antibodies in transfused children with thalassemia in Yunnan province is high. Routine antibody screening should be carried out for transfusion children with thalassemia, and blood units, compatible with ABO, Rh and MNS typing results, should be selected to ensure the safety and effectiveness of clinical blood use.