Point source pollution is a type of pollution that comes from a single, identifiable source of air, water, thermal, noise, or light pollution. This source has negligible extent, which distinguishes it from other pollution source geometries, such as nonpoint source or area source. Point sources are called this way because, in mathematical modeling, they can be approximated as a mathematical point to simplify analysis.

Examples of point source pollution include:

• Air pollution from an industrial source (rather than an airport or a road, considered a line source, or a forest fire, which is considered an area source, or volume source) .
• Water pollution from factories, power plants, municipal sewage treatment plants, and some farms. The U.S. Clean Water Act also defines municipal separate storm sewer systems and industrial stormwater discharges (such as construction sites) as point sources.
• Noise pollution from a jet engine.
• Disruptive seismic vibration from a localized seismic study.
• Light pollution from an intrusive street light.

Point source pollution can be regulated by federal and state agencies, and standards for the quality of water are set based on ways that we use water (beneficial uses) such as drinking, recreation, agriculture, and aquatic life. Point source pollution discharge is limited through NPDES permits to ensure standards of receiving waters are not exceeded.