ObjectiveTo observe the changes of macular choroidal thickness before and after laser treatment for diabetic retinopathy patients. Methods For patients with diabetes by fundus fluorescein angiography (FFA) examination, diagnosed as severe non-proliferative and proliferative diabetic retinopathy and in accordance with the laser photocoagulation treatment indications of 23 patients (45 eyes) included in the study. There were 10 cases of male, 13 cases of female; the average age was (55.48±5.43) years old. All patients underwent macular grid laser photocoagulation and pan-retinal photocoagulation. The macular choroidal thickness before and after laser treatment was measured by enhanced depth imaging technique of optical coherence tomography during follow-up at 1, 2, 3 weeks and one month at specific sites of choroidal. The specific sites included subfoveal choroidal thickness (SFCT), from the foveal 1mm, 3mm, 6mm distance of nasal choroidal thickness (NCT) and temporal choroidal thickness (TCT). ResultsOne week after the treatment, SFCT, NCT1 mm, NCT3 mm, TCT1 mm, TCT3 mm, TCT6 mm were obviously thickening(t=4.728, 4.422, 3.759, 3.743, 5.713, 2.502; P < 0.05). Two weeks after the treatment the SFCT, NCT1 mm, NCT3 mm, TCT1 mm, TCT3 mm were decreased gradually(t=3.189, 2.122, 2.742, 2.196, 2.076; P < 0.05).The choroidal thickness returned to pretreatment level from 2 weeks to 4 weeks after treatment, the NCT6 mm had no obvious change in the whole treatment period(P > 0.05). ConclusionThe choroidal thickness was significantly thicker after laser photocoagulation treatment within 1 week, with the time prolonging the choroidal thickness gradually decreases.