Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and also the main cause of visual impairment or even blindness in diabetic patients. Retinal fibrosis is the leading character of proliferative diabetic retinopathy, which often brings about diabetic tractional retinal detachment. Poly(ADP-ribose) polymerase-1) is the most extensively studied nuclear enzyme of the PARP superfamily, which controls major functions on chromatin, DNA damage repair, and transcriptional regulation. In diabetes, elevated PARP-1 levels were observed in the retina, and inhibition of PARP-1 activity blocks the development of diabetic complications, including neuropathy and retinopathy. More recent studies have shown that PARP-1 might be used as therapeutic biomarkers in diabetic retinopathy. Moreover, mechanistically, studies have revealed the associations between PARP-1 and fibrosis of diabetic nephropathy. Taken together, PARP-1 can be regarded as a therapeutic target not only for diabetic retinopathy, but also for a variety of diabetic retinopathy complications. In the current review, we investigated the recent literature on the roles of PARP-1 in diabetic retinopathy and its potential applications in diabetic diagnosis and prognosis for purpose of developing new strategies for intervention in the diabetic retinopathy.