Objective To study the patient movements features during radiotherapy . Methods Randomly selected 120 patients treated in our hospital from February to July on 2016,including 60 thorax treatment and 60 abdomen treatment. The movement data of patient treatment location during radiotherapy treatment was real time monitored by using Sentinel system,movement features of patient′s location during radiotherapy was analyzed. Paired t-test difference. Results During radiotherapy,patient′s treatment location movement types and proportion were motionless type 14. 0%,Moving stable type 64. 0%,Jumping type 8. 7%,increasing type 13. 3%.Patients with thoracic and abdominal radiotherapy,the maximum deviation of IMRT and VMAT treatment were (6.55±2. 34) mm and (4.97±1. 24) mm (P = 0. 002),(3.97±1. 80) mm and (2.69± 1. 42) mm (P = 0. 004).In single treatment,the deviation value of the patient′s treatment location increased gradually with the treatment time increasing and the deviant of thoracic is greater than abdominal at the same time after the treatment beginning. Conclusions Patient′s treatment location movement during radiotherapy is commonly exist,using the technology of VMAT treatment can effectively reduce the treatment site movement of the patient during the treatment and ensure the accuracy of dose.