Cai Qiao or Chiao Tsai (simplified Chinese: ??; traditional Chinese: ??; pinyin: Cà i Qià o; Wade–Giles: Ts'ai Ch'iao) was a Chinese physiologist and physician.
Cai is famous for his discovery in 1920s, the ventral tegmental area, which also known as the ventral tegmental area of Tsai.
He was elected as a member of Academia Sinica in 1948, also a member of Chinese Academy of Sciences in 1955.