Purpose : Patterns of orbital lymphoma at diagnosis and follow-up are described. We also discuss differential diagnosis of orbital masses. ; Materials and methods : This pictorial review contains 19 cases of orbital lymphoma before and after treatment. Superior-lateral quadrant and extra-conal location were observed predominantly. Effective response after treatment was presented on follow-up imaging, although few local relapses were found. Further follow-up showed no changes of residual images. ; Discussion : Location of orbital masses can help in the differential diagnosis. Moreover, imaging features of lymphoma at diagnosis can be useful in planning surgical biopsy. Pattern of follow-up described may be relevant on monitoring imaging. ; Teaching points : • Orbital lymphoma involves mainly superior-lateral quadrant and the orbital structures inside.• Location of retrobulbar mass-like lesions are useful information in the differential diagnosis.• Satisfactory response is detected after treatment, however relapse is noted, so follow-up is needed.