The direct current regulated power supply adopting the mechanical buttons programming mode has problems, such as easy wear of buttons and complex circuit composition. To solve the above problems, a system is designed with the programmable digital power supply TFT liquid crystal display (LCD) screen touch display based on STM32F7. In terms of the hardware of the system, it is composed of an STM32F7 processor, TFT LCD touch screen, SDRAM chip, and power supply module. STM32F7 is used to drive TFT LCD screen and to expand external SDRAM as video memory through LTDC, and the power supply module provides backlight voltage power for the display screen. The software uses the real-time operating system of FreeRTOS for managing and dispatching system tasks, utilizes emWin for interface design, and adopts DMA pattern to read data. The display system has a simple circuit, stable and reliable display performance, and can control the power system by touching. The experimental results show that the system has a clear display effect, fast control and response. Additionally, the system realizes the human-computer interaction function of the programmable power supply by utilizing the TFT touch screen, thereby providing a reference for the application of the TFT touch screen in the power supply field.