Objective To explore the nursing effects of self-care body posture in patients after modified radical mastectomy. Methods The clinical data of 102 patients with modified radical mastectomy were randomly divided into the study group and the control group, all patients met the following standard:clear consciousness, effective communication, no paralysis of limbs, no fracture. In the study group, according to Orem"self-care theory" concept, patients carried out self-care body posture with mainly focus on self-emancipated and the body center of gravity position, in the control group patients were given traditional posture care with mainly emancipated assistance. The first time getting out-of-bed, the occurrence of various complications, the comfort level of emancipation and posture, as well as nursing satisfaction on the first day after surgery were observed and compared between the two groups. Results The two groups showed significant difference in the first time out-of-bed, anxiety, the comfort level of emancipation and posture, as well as nursing satisfaction. There was no significant difference between the two groups in dizziness, limb swelling, flap effusion, flap necrosis. No pressure ulcer occurred. Conclusions Making use of self-care body posture in patients after modified radical mastectomy can improve the satisfaction and comfort of the patients, and improve the patients' recovery, without increasing the complication, which is worth promoting.