Purpose: To report a case of unilateral diffuse uveal melanocytic proliferation, in a patient with history of breast cancer, with bone and hepatic metastasis.Methods: Case report with funduscopic examination, fundus autofluorescence, and spectral-domain optical coherence tomography.Results: A 57-year-old female patient attended at our clinic for a routine glaucoma follow-up. Fundoscopy was normal on the right eye and showed multiple red patches in the posterior pole and inferior arcade. Multimodal examination was performed, compatible to diffuse uveal melanocytic proliferation on her left eye, and excluding other conditions, such as choroidal metastasis.Conclusion: Diffuse uveal melanocytic proliferation is a rare paraneoplastic condition, which usually is presented bilaterally. Unilateral cases of diffuse uveal melanocytic proliferation have been previously described only 5 times on the literature and are usually associated with breast cancer.