Objective: To summarize the clinical and pathological characteristics of IgG4-related ophthalmic disease (IgG4-ROD) involving the lacrimal gland. Methods: A retrospective case series study. Forty cases (56 eyes) of lacrimal gland lesions were collected in Tianjin Eye Hospital from January 2003 to January 2018 and confirmed by histopathology as lymphocyte and plasma cell infiltration with fibrosis of lacrimal gland tissue, excluding lymphoma, epithelial tumor, mesenchymal tumor and metastasis tumor. The clinical manifestations, serological and imaging examination of the patients were analyzed. Meanwhile, HE staining and immunohistochemical staining of IgG and IgG4 were performed on the pathological specimens. According to the diagnostic criteria, the cases were divided into the IgG4-ROD group and the non-IgG4-ROD group. The clinical and pathological characteristics of the two groups were statistically analyzed by Pearson chi-square and signed-rank test. Results: In the 40 cases (56 eyes), there were 15 cases (25 eyes) of IgG4-ROD and 25 cases (31 eyes) of non-IgG4-ROD. Statistically significant differences were observed between the two groups in the clinical and pathological characteristics (all P<0.05). About the distribution of eyes position, there were 10 binocular cases and 5 monocular cases in the IgG4-ROD group, and 6 binocular cases and 19 monocular cases in non-IgG4-ROD group (χ2=7.111).There were 21 eyes in the IgG4-ROD group and 5 eyes in the non-IgG4-ROD group about ptosis (χ2=25.631), 4 eyes in the IgG4-ROD group and 21 eyes in the non-IgG4-ROD group about ocular protrusion (χ2=14.992), 23 eyes in the IgG4-ROD group and 15 eyes in the non-IgG4-ROD group about the clear boundary of the tumor (χ2=12.069), 4 eyes in the IgG4-ROD group and 18 eyes in the non-IgG4-ROD group about the involvement of other orbital tissues (χ2=10.266) and 7 cases in the IgG4-ROD group and 3 cases in the non-IgG4-ROD group about the association with other systemic diseases (χ2=6.009). Compared with the non-IgG4-ROD group, the IgG4-ROD group had a heavier lymphocyte and plasma cell infiltration (+++,++,+; 10, 4, 1 vs. 6, 5, 12 eyes, Z=-3.153), and more lymphoid follicles (+++,++,+; 3, 6, 4 vs. 1, 2, 7 eyes, Z=-3.339), interstitial fibrosis was mostly striate (10 vs. 5 eyes, χ2=8.711), and there were a large number of IgG4+ plasma cells [96 (67, 135) vs. 4 (0, 12) cells per high power field, Z=-5.271] and ratio of IgG4+ plasma cells/IgG+ plasma cells [0.570 (0.500, 0.754) vs. 0.046 (0.000, 0.143), Z=-5.268, all P<0.05). Among the 10 cases of IgG4-ROD with serological examination, 9 cases showed elevated serum in IgG and IgG4. The ultrasonography and CT findings showed the lacrimal gland lesions in the IgG4-ROD group were mostly spindle or kidney shaped with clear boundaries, while the lesions in non-IgG4-ROD were mostly round or irregular with unclear boundaries. Conclusions: The lacrimal gland lesions of IgG4-ROD are characterized by bilaterally spindle or kidney shaped enlargement with clear boundaries. They are more associates with other systemic diseases. The pathological characteristics are a large number of IgG4+ plasma cells infiltration among the lacrimal gland tissue, interstitial striate fibrosis and a large number of lymphoid follicles. (Chin J Ophthalmol, 2019, 55: 834-841).