The aim of the study was to compare intravitreal bevacizumab (IVB) and posterior subtenon triamcinolone (PST) as an adjunct to laser treatment in diffuse diabetic macular edema (Diffuse DME). Prospective-randomized control trial of 30 eyes of 30 diabetic patients having Diffuse DME with maximum retinal thickness (MRT) was more than or equal to 350 µm. The subjects were randomly allocated into two groups. Group A (12 eyes) received IVB and group B received PST (18 patients) before laser treatment. Grid laser treatment was done when the MRT decreased to less than 350 µm. OCT thickness-guided repeat injections were given if required. The patients had minimum follow-up of 6 months. At 6-month follow-up, the two groups were compared for (1) Maximum change in visual acuity letter score using logMAR chart (2) Reduction in MRT on OCT. The mean logMAR visual acuity at baseline was 0.63 ± 0.45 (0-1.6) in group A and was 0.76 ± 0.38 (0.2-1.3) in group B. The mean logMAR visual acuity at 6 month in group A was 0.34 ± 0.21 (0-0.6) and in group B was 0.64 ± 0.37 (0.3-1.3). The mean visual acuity at last follow-up was significantly better in group A than group B (p = 0.02). The mean change in MRT in Group A and Group B was 177.8 ± 85.64 and 156.07 ± 102.86, respectively, which was significantly better than the baseline in both the groups and was comparable in both groups. The study provides evidence to support the use of IVB over PST in diffuse diabetic macular edema.