Nikkor is the brand of lenses produced by Nikon Corporation, including camera lenses for the Nikon F-mount and more recently, for the Nikon Z line of mirrorless cameras.

The Nikkor brand was introduced in 1932, a Westernised rendering of an earlier version Nikkō (日光), an abbreviation of the company's original full name Nippon Kōgaku ("Japan Optics"; 日本光学工業株式会社). (Nikkō also means "sunlight" and is the name of a Japanese town.) In 1933, Nikon marketed its first camera lens under the Nikkor brand name, the "Aero-NIKKOR," for aerial photography.

Nikon originally reserved the Nikkor designation for its highest-quality imaging optics, but in recent history almost all Nikon lenses are so branded.

Notable Nikkor branded optics have included:

Nikon introduced the Z-mount in 2018 for their system of digital full-frame and APS-C (DX) mirrorless cameras. All of Nikon's Z-mount lenses are Nikkors.

Nikkors constitute the majority of lenses available for the Nikon F-mount, which is itself the largest system of interchangeable flange-mount photographic lenses in history^{[clarification needed]}. These lenses are designed for the 135 (35mm) and Nikon DX formats. Over 400 different F-mount Nikkor models are known to exist.

Nikon introduced the compact mirrorless Nikon 1 camera system using 2.7x-crop sensors in 2011. The Nikon 1 system was effectively discontinued in 2018 with the introduction of the full-frame Nikon Z system.

The original Nikonos system introduced in 1963 is a scale-focus and rangefinder system for underwater photography. The 1992 Nikonos RS system is an underwater autofocus SLR system based on the F-mount.