An apparatus and a method for analyzing a flexion of a knee joint relate to a method for detecting flexing frequency, angle and speed of a knee joint. The apparatus is an transmitter, and comprises an upper transmitter, a lower transmitter and a positioning transmitter. The signals measured by each of the transmitters are transmitted to a receiver, and the message is transmitted to the preset software of a computer or a mobile device by the receiver for analysis to know a flexing angle message and the number of the knee joint, so as to improve the mastery of a doctor to the flexing motion of the knee joint of a user. Furthermore, by detecting the flexing angle of the knee joint, he angle of force application and the degree of rehabilitation of the knee joint may be awared and the rehabilitation efficiency can be improved.一種膝關節彎曲狀態之分析裝置及其方法,係關於一種檢測膝關節彎曲次數、角度及速度的一種方法;裝置為發射器,係包括上發射器、下發射器及定位發射器,透過各發射器所測得之訊號傳送至接受器,並將訊息由接受器再傳至電腦或行動裝置之預設軟體上做分析以得知膝蓋彎曲角度訊息及次數,提高醫生對於使用者膝關節彎曲運動的掌握度;更進一步,可經由膝關節彎曲的角度檢測,得知膝關節的施力角度及復健程度,進而提高復健效率。10‧‧‧定位發射器20‧‧‧接受器