The aim was to investigate the effects of combined red and infrared lasers on histopathology collagen formation in diabetic foot ulcer (DFU). Forty-five DFU patients both sexes, age range of 18–60 years were divided randomly into three equal groups. Laser group (A) received laser therapy in sequential beam mode, while (B) received laser therapy in separate beam mode. The control group only received conventional wound management, which was also provided to both the laser and the exercise groups. All laser groups were offered 12 sessions over 8 week inform of 2 sessions of laser therapy/ week in 1st month and one session/ week in the 2nd month. Wound surface area (WSA), the percentage of complete healing and collagen formation percent were evaluated pre- and post-treatment. Statistical significance was set at P < 0.05. There was a significant decrease within all the groups’ comparison, and there was a significant decrease in WSA of group A compared with that of group B and group C post treatment (p < 0.001). There was a significant decrease in WSA of group B compared with group C post treatment (p < 0.01). The percentage of complete healing in group A, B and C was 60%, 13.3% and 0% respectively. There was a significant increase in the percentage of complete healing in group A compared with group B and C (p < 0.001), which indicate the increase of collagen formation due to the healing process of DFU and illustrated by histopathology pictures. Sequential mode in group (A) and with separate mode beam group (B) were found to be the most effective methods for DFU healing by decrease wound surface area, with sequential mode beam group (A) offering superior performance in the percentage of complete healing and collagen formation percent in the management of DFU.