Born in 1539 in Nanao, Noto Province (today Nanao, Ishikawa), as the child of the Okumura family of dyers. His childhood name was Matashiro, later Nobuharu. Adopted by Hasegawa Muneharu, he took the Hasegawa surname. In his youth he painted Buddhist paintings and portraits related to the Nichiren sect in Noto, working under the name 'Nobuharu.' Around 1571, aged 33, he went up to Kyoto. He learned the techniques of the Kano and Tosa schools and thoroughly studied Chinese Song-Yuan painting (especially Muqi and Liang Kai). He also became friends with Sen no Rikyu and deepened the spirituality of ink painting through the tea ceremony. Around 1590, by Hideyoshi's order he painted 'Landscape Fusuma' for Sangen-in at Daitoku-ji. In 1591, after the sudden death of Kano Eitoku, when Hideyoshi built Shoun-ji (today Chishaku-in) as a memorial temple for his late beloved son Tsurumatsu, the Hasegawa school received the commission and produced large gold-ground works such as 'Maple' and 'Pine with Autumn Grasses' (National Treasures, Chishaku-in). In 1593 his eldest son Kyuzo died suddenly at 26. In his grief, around 1595 he is said to have produced his ink-painting summit 'Pine Forest Screen.' He was given the Hokkyo rank in 1605 and Hogen in 1610. That same year he died in Kyoto at 72 while on his way down to Edo by Ieyasu's order.

A late-bloomer who rose from provincial painter in Noto to the top of the Kyoto art world. While the Kano school reigned as the orthodox of court and warrior, he mastered the ink techniques of Song-Yuan painting by self-study and founded the original 'Hasegawa style.' As symbolized by his friendship with Sen no Rikyu, he deeply understood the spirituality of tea and Zen.

The Hasegawa school flourished in the Azuchi-Momoyama period as a rival to the Kano school. Yet Tohaku's own 'Pine Forest Screen' (National Treasure, Tokyo National Museum) occupies an unshakable position as the supreme masterpiece of Japanese ink painting and leaves its name in world art history. The wall paintings of Chishaku-in (National Treasure) are also representatives of Momoyama wall painting. The Nanao Art Museum (Nanao, Ishikawa), as his birthplace, holds related works and materials and is the center of his research.