Objective To study evaluation analysis of lung cancer with brain metastasis patients after stereotactic radiotherapy MRI change condition and for short-term effect. Methods 62 cases of patients were chosen as the research object from January 2010 to December 2013 in our hospital to accept the treatment of brain metastases of lung cancer. All patients were given with SRT, after treatment analysis of patients with recent curative effect and changes of MRI, time and suspicious recurrence progress of contrast. Results 62 cases of patients with 120 lesions, after treatment of CR lesions accounted for 25%, PR lesions accounted for 15%, CR+PR efficiency was 40%. 120 lesions, after the treatment of SRT recurrence in 28, of which 26 lesions after salvage treatment volume increased, 12 was as nodular enhancement, 14 was heterogeneous enhancement. Suspicious progress was 22. Focus control 70, of which 12 volume than before treatment slightly larger lesions, 10 smooth or flower ring enhancing lesions, 2 heterogeneous enhancement and no obvious peritumoral edema and mass effect of the lesions. The median time to relapse at a median time of lesions was significantly less suspicious progression; the difference was statistically significant (P<0.05). Conclusion The patients of brain metastases from lung cancer treated with SRT imaging findings are various, for thick wall and nodular, and inhomogeneous enhancement etc. shall determine the therapy effect of SRT therapy, the clinical observation in symptomatic and basis for other classes with the diagnosis of inspection tools.