Electronic waste recycling, electronics recycling, or e-waste recycling is the disassembly and separation of components and raw materials of waste electronics; when referring to specific types of e-waste, the terms like computer recycling or mobile phone recycling may be used. Like other waste streams, reuse, donation, and repair are common sustainable ways to dispose of information technology (IT) waste.

Since its inception in the early 1990s, more and more devices are being recycled worldwide due to increased awareness and investment. Electronic recycling occurs primarily to recover valuable, rare-earth metals and precious metals, which are in short supply, as well as plastics and metals. These are resold or used in new devices after purification, in effect creating a circular economy. Such processes involve specialised facilities and premises, but within the home or ordinary workplace, sound components of damaged or obsolete computers can often be reused, reducing replacement costs.

Recycling is considered environmentally friendly because it prevents hazardous waste, including heavy metals and carcinogens, from entering the atmosphere, landfill, or waterways. While electronics make up a small fraction of total waste generated, they are far more dangerous. There is stringent legislation designed to enforce and encourage the sustainable disposal of appliances, the most notable being the Waste Electrical and Electronic Equipment Directive of the European Union and the United States National Computer Recycling Act. In 2009, 38% of computers and a quarter of total electronic waste were recycled in the United States, 5% and 3% up from 3 years prior, respectively.

Obsolete computers and old electronics are valuable sources for secondary raw materials if recycled; otherwise, these devices are a source of toxins and carcinogens. Rapid technology change, low initial cost, and planned obsolescence have resulted in a fast-growing surplus of computers and other electronic components around the globe. Technical solutions are available, but in most cases a legal framework, collection system, logistics, and other services need to be implemented before applying a technical solution. The U.S. Environmental Protection Agency, estimates 30 to 40 million surplus PCs, classified as "hazardous household waste", would be ready for end-of-life management in the next few years. The U.S. National Safety Council estimates that 75% of all personal computers ever sold are now surplus electronics.

In 2007, the United States Environmental Protection Agency (EPA) stated that more than 63 million computers in the U.S. were traded in for replacements or discarded. Today, 15% of electronic devices and equipment are recycled in the United States. Most electronic waste is sent to landfills or incinerated, which releases materials such as lead, mercury, or cadmium into the soil, groundwater, and atmosphere, thus having a negative impact on the environment.

Many materials used in computer hardware can be recovered by recycling for future production. The reuse of tin, silicon, iron, aluminium, and a variety of plastics that are present in bulk in computers or other electronics can reduce the costs of constructing new systems. Components frequently contain copper, gold, tantalum, silver, platinum, palladium, and lead as well as other valuable materials suitable for reclamation.

Computer hardware contains many toxic substances, like dioxins, polychlorinated biphenyls (PCBs), cadmium, chromium, radioactive isotopes, and mercury. A typical computer monitor may contain more than 6% lead by weight, much of which is in the lead glass of the cathode-ray tube (CRT). A typical 15-inch (38 cm) computer monitor may contain 1.5 pounds (1 kg) of lead, but other monitors have been estimated to have up to 8 pounds (4 kg) of lead. Circuit boards contain considerable quantities of lead-tin solders that are more likely to leach into groundwater or create air pollution due to incineration. In US landfills, about 40% of the lead content levels are from e-waste. The processing (e.g., incineration and acid treatments) required to reclaim these precious substances may release, generate, or synthesize toxic byproducts.

Export of waste to countries with lower environmental standards is a major concern. The Basel Convention includes hazardous wastes such as, but not limited to, CRT screens as an item that may not be exported transcontinentally without the prior consent of both the country exporting and receiving the waste. Companies may find it cost-effective in the short term to sell outdated computers to less developed countries with lax regulations. It is commonly believed that a majority of surplus laptops are routed to developing nations. The high value of working and reusable laptops, computers, and components (e.g., RAM) can help pay the cost of transportation for many worthless commodities.^{[clarification needed]} Laws governing the exportation of waste electronics are put in place to govern recycling companies in developed countries, which ship waste to Third World countries. However, concerns about the impact of e-recycling on human health, the health of recycling workers, and environmental degradation remain. For example, due to the lack of strict regulations in developing countries, sometimes workers smash old products, propelling toxins onto the ground, contaminating the soil, and putting those who do not wear shoes in danger. Other procedures include burning away wire insulation and acid baths to resell circuit boards. These methods pose environmental and health hazards, as toxins are released into the air and acid bath residue can enter the water supply.