Radionics (also called electromagnetic therapy (EMT)) is a form of alternative medicine that claims disease can be diagnosed and treated by applying electromagnetic radiation (EMR), such as radio waves, to the body from an electrically powered device. It is similar to magnet therapy which also applies EMR to the body, but using a magnet that generates a static electromagnetic field.

The concept behind radionics originated in the early 1900s with Albert Abrams (1864–1924), who became a millionaire by leasing radionic machines which he designed himself. Radionics contradicts the principles of physics and biology and, as such, is widely considered pseudoscientific. The United States Food and Drug Administration does not recognize any legitimate medical uses for radionic devices.

Several systematic reviews have shown radionics is no more effective than placebo and falls into the category of pseudoscience.