A straight-tube UV light. The straight-tube UV light includes a light body, end covers, and functional subassemblies. The light body is of a hollow tubular structure provided in a straight line; the end cover includes a first end cover and second end cover provided on a left and right of the light body, the first end cover, the second end cover and the light body enclose to form a mounting cavity. The functional subassemblies include at least the first light source subassembly and the control power supply, provided inside the mounting cavity, the control power supply controls the first light source subassembly to emit UV rays for sterilization and disinfection. This can simplify the protective structure of the light, reduce the volume of the light, and improve a sealing property of the light.