Hisamitsu Pharmaceutical Co is a Japanese pharmaceutical company headquartered in Tokyo and Saga. The company develops and markets drugs. Painkillers are the hallmark of production, which are sold both in the Japanese and foreign markets. Products are exported to more than fifty countries around the world.

Hisamitsu was founded in 1847 under the name Komatsuya in present-day Tosu, which borders Saga Prefecture and Fukuoka in Kyushu. This area is well known in Japan for traditional herbal medicines.

Hisamitsu Pharmaceutical sponsors the Hisamitsu Springs professional volleyball team. During training and competition, athletes use the company's products to maintain energy and performance.