AIM: To analyze the 5-year disease-free survival (DFS) of primary orbital lymphoma (POL) by clinical characteristics and imaging features. METHODS: A total of 72 patients, 43 males and 29 females, with histologically confirmed POL, were retrospectively recruited between January 2012 and May 2017. The information on clinical characteristics, imaging features, and 5-year DFS was obtained. Univariate and multivariate forward logistic regression analyses were used to identify the variables significantly associated with 5-year DFS. Kaplan-Meier was applied for survival analysis. RESULTS: Univariate analysis revealed that uni- or bilateral orbital involvement, single or multiple lesions, treatment methods, and contrast enhancement pattern on images were significant for 5-year DFS (P=0.022, 0.042, <0.001, and 0.028, respectively), while in multivariate logistic regression analysis, only uni- or bilateral orbital involvement, treatment methods and contrast enhancement pattern on images were significant (r=0.453, 0.897, and 0.556, P=0.038, <0.001 and 0.022, respectively). The survival curves for DFS were obtained. CONCLUSION: The majority of POL are B-cell lymphomas. Unilateral orbital involvement, homogeneous contrast enhancement on images, and the appropriate treatment schemes result to be significant factors for a good prognosis for POL.