The aim of this study was to investigate the primary sites, clinical characteristics, and treatment outcomes of patients with metastatic tumors in the eye and ocular adnexa. This retrospective case series consisted of 42 patients diagnosed with intraocular metastasis (IM) or ocular adnexal metastasis (OAM) at a tertiary center between January 2001 and June 2023. The patients comprised 18 men and 24 women; 24 (57%) and 18 (43%) patients were diagnosed with IM and OAM, respectively. In the IM group, the primary tumors originated from the lungs (79%), followed by the breasts (17%). In the OAM group, the primary tumors originated from the breasts (33%). Previously, 57% of the patients had been diagnosed with cancer. In the IM group, 38% exhibited bilateral involvement. Only 6% of the patients with OAM had bilateral diseases. The 1-, 3-, and 5-year overall survival (OS) was 42%, 18%, and 7%, respectively. The median OS since metastasis diagnosis in the lungs and breast was 11.8 and 10.5 months, respectively. Lung cancer remains the predominant primary cancer in IM, whereas breast cancer is the major cancer in OAM. Despite poor OS, early detection will facilitate the prompt treatment of primary cancer and metastatic sites.