BACKGROUND: Wound healing in diabetic foot ulcers (DFUs) is challenging and often requires extensive debridement and in some cases leads to amputation. Negative-pressure wound therapy (NPWT) can be utilized for DFUs. The optimal time frame for successful NPWT lacks consensus. Advanced wound scanning with a three-dimensional (3D) camera can enhance accuracy of DFU area and volume calculations. This study aimed to investigate the utility of 3D wound assessment in monitoring granulation tissue filling velocity with NPWT in DFUs. METHODS: A retrospective case series study was performed for 101 DFUs (Wagner classification 3 or 4 lesions with significant necrotic tissue debridement failing to achieve primary closure, leading to open amputation) undergoing NPWT from September 2018 to June 2019. Demographic data and wound characteristics were recorded. Before application of NPWT, wounds were irrigated after extensive procedures, and digital photographs of the wound were captured using an infrared 3D camera. Wound area and volume were measured weekly from before the application of NPWT to 1 month after. Risk factors associated with wound healing in DFUs were also evaluated. RESULTS: NPWT resulted in significant area improvements for open DFUs. Postoperative 1-week area change velocity was 1.35 cm CONCLUSION: 3D wound assessment for the velocity of granulation tissue filled in an open DFU after NPWT can be useful for monitoring healing progression. Most wound healing following NPWT in DFUs was completed within the first 2 weeks.