This paper proposed to evaluate the tear fluid mucin 5AC (MUC5AC) change in Chinese primary angle-closure glaucoma and cataract patients after short-term medications and phacotrabeculectomy.Twenty-five eyes of 25 consecutive Chinese patients with coexisting visually significant cataract and angle-closure glaucoma and 40 eyes of 40 volunteers enrolled in this study were investigated. Tear fluid from normal subjects and patients (1 day pre-operatively, 1 month, 3 months, and 6 months post-operatively, respectively) were collected. The MUC5AC protein levels in the tear fluid were determined by Enzyme-Linked ImmunoSorbent Assay (ELISA). The MUC5AC change after phacotrabeculectomy was evaluated.The MUC5AC quantity of the patients after short-term medications was 16.95±12.86 ng/ml, compared with 32.39±18.44 ng/ml MUC5AC quantity of the controls. There was a significant difference between the two groups (p<0.05). The MUC5AC of the patients decreased significantly to 6.91±7.11 ng/ml at 1 month after surgery (p<0.05). At 3 months after surgery, the MUC5AC recovered to 15.53±12.63 ng/ml, and had no significant difference with the pre-operative level (p=0.26). At 6 months after surgery, the MUC5AC was 18.94±14.64 ng/ml and had no significant difference with before-surgery levels (p=0.14).Both phacotrabeculectomy and short-term anti-glaucoma medications can decrease the MUC5AC in the tear fluid of primary angle-closure glaucoma patients. At 3 months after phacotrabeculectomy, the MUC5AC could recover to the pre-operative level. More attention should be paid to the tear film stability and ocular surface physiology in these patients.