Background Dry eye is a multifactorial disease of the tears and the ocular surface. This study aimed to investigate the clinical efficacy of a non-steroidal anti-inflammatory drug, pranoprofen, in the treatment of dry eye. Methods It is a prospective, multi-center, randomized, controlled, parallel group study. One hundred and fifteen patients with mild to moderate dry eye disease (55-60 in each treatment group) participated in this multi-center study. Patients were randomly administered with eyedrops containing 0.1% pranoprofen (PRA) plus 0.1% sodium hyaluronate (SH) or SH only, three times daily for 28 days, followed by a 1-week after treatment observation. Dry eye symptom score (DESS), fluorescein corneal staining (FLCS), tear break-up time (TBUT), and Shirmer 1 tear test (ST1, without anesthesia) were evaluated or conducted before treatment and at each study visit. Conjunctival impression cytology was taken from the patients treated with PRA plus SH before and after treatment and real-time polymerase chain reaction (RT-PCR) was performed to detect the changes of human leukocyte antigen DR (HLA-DR) and intercellular adhesion molecule 1 (ICAM-1). Results Patients treated with PRA plus SH showed gradual improvements of DESS, FLCS, and TBUT. Between-group comparisons of FLCS and TBUT have statistically significant differences from day 14. Good tolerance with no severe adverse events was found in both groups. Patients treated with PRA plus SH had a reduced expression level of HLA-DR and were statistically different after 28 days of therapy. Conclusions The application of PRA at a dose of 0.1% was well tolerated and benefited to the patients with mild to moderate dry eye disease. The underlying mechanism of its efficacy may be associated with the reduction of inflammatory factors of conjunctival epithelial cells.