Hoya Corporation (HOYA株式会社, Hoya Kabushiki Gaisha^?) is a leading Japanese company manufacturing optical products such as photomasks, photomask blanks and glass magnetic-memory disks, contact lenses and eyeglass lenses using the wavefront technology for the health-care market, medical photonics, lasers, photographic filters, and software. The headquarters are in 2-7-5 Naka-Ochiai, Shinjuku, Tokyo. Hoya Corporation is one of the Forbes Global 2000 Leading Companies and Industry Week 1000 Company .

Hoya acquired the camera company Pentax in 2007, for the price of US$1 billion, about 10% more than Pentax was valued at the time. In June 2010 the grandson of the corporation's founder Yutaka Yamanaka proposed changes to the Board of Directors to prevent what he called such "mistakes" from happening again.

On October 1, 2011, Hoya sold its Pentax camera business to Ricoh.

Hoya discussed a merger with Pentax into Hoya Pentax HD Corporation during 2007. Hoya's primary goal was to strengthen its medical-related business by taking advantage of Pentax's technologies and expertise in the field of endoscopes, intraocular lenses, surgical loupes, biocompatible ceramics, etc. It was speculated that Pentax's camera business could be sold off after the merger. The merger was initially intended to be completed by October 1, 2007. However, Pentax management decided to not pursue the originally planned share swap, and other options for a merger were discussed. On May 25, the Pentax board of directors accepted Hoya's offer for a merger. On August 6, 2007, Hoya completed a friendly takeover bid for Pentax and acquired 90.59% of the company. On October 29, 2007, Hoya and Pentax announced that Pentax, as the company ceasing to exist, will merge with and into Hoya on March 31, 2008. Hoya will retain the Pentax brand name and reports $2,927.3 (mil) in sales.