There are two small types of the Formosan Mountain Dog; one is about 40 centimetres (16 in) tall at the shoulder and the other is around 30 centimetres (12 in). However, the latter one was not found during the research conducted by Dr. Sung Yung-yi (宋永義) in 1976. The medium type of the Formosan Mountain Dog has a shoulder height under 50 centimetres (20 in), with a firm and fit body, slim waist, big chest and half-covered ears.