WHD may refer to:
- World Health Day, a public health education day designated by the World Health Ogranzation.
- Wafer Handling Diffusion, a machine used to load/unload solar wafers into/from a diffusion furnace.
- World Humanitarian Day, a day designated by the United Nation.
- Wage and Hour Division, a division of the United States Department of Labor.
- WHD-TV, a defunct experimental digital television station.
- Werdnig–Hoffmann disease, an infantile-onset type of spinal muscular atrophy.