Purpose：The hamstring muscle has an important role in standing, walking and other functions related to daily living. Most people with Cerebral Palsy(CP) have muscle tightness, especially in the hamstring, which may cause abnormal alignment in the lower extremities. To investigate an effective treatment for hamstring muscle tightness by observing the effects of heat pack or Soft tissue mobilization(STM) on hamstring muscles. Methods：Thirteen-two volunteers with CP aged between 9 and 13 years($MpmSD$: $11pm1.46$), were recruited and divided into four groups of four: (1) the STM for people with Spastic CP group, (2) the heat pack(HP) for people with Spastic CP group, (3) the STM for people with Mixd CP group, and (4) the heat pack for people with Mixed CP group. All received treatment three times per week for six weeks. A inclinometer was used to measure for hip flexion & knee extension joint range motion(ROM). Results：The ROM of hip flexion & knee extension were improved at the STM and HP for people with Spastic CP groups. The ROM and hip flexion were improved at the STM and HP for people with Mixed CP groups. The amount of increase ROM are differenced by the types of CP. Conculusion：STM and heat pack, both are effective for people with CP especially for Spastic CP.