Ten Bulls or Ten Ox Herding Pictures (Chinese: shíniú 十牛 , Japanese: jūgyūzu 十牛図 , korean: sipwoo 십우) is a series of short poems and accompanying drawings used in the Zen tradition to describe the stages of a practitioner's progress toward awakening, and their subsequent return to society to enact wisdom and compassion. Inspired by Indian Buddhist teachings, the pictures emerged in Song Dynasty China and spread among the Chan/Zen tradition throughout East Asia.

The calf, bull, or ox is one of the earliest similes for meditation practice. It comes from the Maha Gopalaka Sutta (Majjhima Nikaya 33). It is also used in the commentaries, especially the one on the Maha Satipatthana Sutta (Digha Nikaya 22) and the Satipatthana Sutta (Majjhima Nikaya 10). In Indian Buddhism, the simile of the bull is compatible to the ancient traditional Chinese view within cosmology that includes the zodiacal Ox (niú 牛) as a birth year and quality, as a result this similarity helped with the early assimilation of Buddhism into Chinese culture and then on to the rest of East Asia. Buddhaghosa, in his commentary on the Satipatthana Suttas, gives a simile of the taming of a wild calf. The calf is the wild mind which is to be tamed. The same idea was developed by the Chan/Zen tradition.

The well-known ten ox-herding pictures emerged in China in the 12th century. D.T. Suzuki mentions four Chinese versions of the Ten Bulls, by Ching-chu (Jp. Seikyo, c. 11th century), Tzu-te Hui (Jp. Jitoku, c. 1090-1159), an unknown author, and Kuoan Shiyuan (Jp. Kaku-an) (c. 12th century).

The first series was probably made by Ching-chu in the 11th century, who may have been a contemporary of Kuòān Shīyuǎn. There are only five pictures in Ching-chu's version and the ox's colour changes from dark to white, representing the gradual development of the practitioner, ending in the disappearance of the practitioner.

Tzu-te Hui (自得慧暉, Zide Huihui; Jp. Jitoku ki) (1090-1159) made a version with six pictures. The sixth one goes beyond the stage of absolute emptiness, where Ching-chu's version ends. Just like Ching-chu's version, the ox grows whiter along the way.

A third version by an unknown author, with ten pictures, was the most popular in China. It derives from the Ching-chu and Tzu-te Hui series of pictures, and has a somewhat different series of pictures compared to Shiyuan's version. The 1585 edition contains a preface by Chu-hung, and it has ten pictures, each of which is preceded by Pu-ming's poem, of whom Chu-hung provides no further information. In this version, the ox's colour changes from dark to white.

The most famous version of the oxherding pictures was drawn by the 12th century Chinese Rinzai Chan/Zen master Kuoan Shiyuan (廓庵師遠, Kuòān Shīyuǎn; Jp. Kaku-an Shi-en), who also wrote accompanying poems and introductory words attached to the pictures. In Shiyuan's version, there is no whitening process, and his series also doesn't end with mere emptiness, or absolute truth, but shows a return to the world, depicting Budai ("Laughing Buddha"), who is the bodhisattva Maitreya.

Liaoan Qingyu (了菴清欲, Jp. Ryōan Seiyoku) (1288-1363) made another version with five pictures.