The purpose of this study was twofold:(1)to analyze the effect of teachers'multiple thinking teachingstrategy under the help of supervision;and(2)to explore the process of teachers'professional growth.Theparticipants used in this study were 74 elementary school students,one supervisor,one experimental groupteacher,and one control group teacher.The instruments administered to the subjects were Teaching Programof Mathematics Multiple Thinking Teaching Strategy,Mathematics Achievement Tests,Notebook ofMathematics Learning,a Teaching Diary,and Classroom Observation Records.The findings were as follows:(1)There was a significant difference in mathematics performance between the experimental and controlgroups on the mathematics achievement test,with the experimental group scoring higher than that of controlgroup.(2)According to students'notebooks,they showed that they liked the multiple thinking teachingstrategy.(3)In the process of group discussion,students obtained the problem-solving methods that were notlisted on the textbook.(4)Teachers should participate in study meeting,discussion,practical teachings andreflection to promote their professional abilities,and(5)The teachers'professional growth process seems toinclude eight stages:imagination,frustration,habit,activation,thinking,trying,modification,and promotion.