He was born into a branch of the Ryukyuan royal family, and at the age of 12, he and his older brother Motobu Chōyū were invited by Ankō Itosu to be taught karate.

Motobu Chōki was born in 1870 in Shuri Akahira, the capital of the Ryukyu Kingdom, the third son of father Chōshin and mother Ushi.

He studied karate primarily under Ankō Itosu (1831 - 1915), Sōkon Matsumura (1809 - 1899), Sakuma, and Kōsaku Matsumora (1829 - 1898), but also occasionally under Kunjan Pēchin and Kuniyoshi Shinkichi.

Therefore, he secretly continued his training under Sōkon Matsumura and Sakuma from Shuri, and by the time he was over 20 years old, he was confident that he could defeat his brother in kumite.

[7] From the age of 19 or 20, Motobu, along with his older brother Chōyū and his friend Kentsū Yabu, began studying under Kōsaku Matsumora.

According to an account of the fight from a 1925 King magazine article, Motobu is said to have entered into a challenge match with a tall, burly foreign boxer called George.

[13] Taking advantage of this, after a few rounds, according to the account, Motobu moved in on the taller, larger boxer and knocked him out with a single hand strike to the head.

The King article detailed Motobu's surprising victory, although the illustrations clearly show Funakoshi Gichin as the Okinawan fighter in question.

The popularity generated by this unexpected victory propelled both Motobu and karate to a degree of fame that neither had previously known in Japan.

Around 1927, Motobu moved to Tokyo to establish the Daidōkan dojo and also became the first Shihan of the karate club at Toyo University.

In a Tsunami video production on Motobu-ryū, Motobu Chōsei comments that his father's language difficulties may have been motivated more by protest at being a displaced member (by the Japanese annexation of Okinawa) of the Ryukyuan aristocracy than by inability.

Motobu occasionally traveled to Tokyo to teach karate, but due to deteriorating health he closed his dojo in the fall of 1941 and returned to Osaka.

On January 7, 1927, Motobu demonstrated wood-board breaking and kumite in front of Kanō Jigorō, the founder of judo, who was visiting Okinawa.

[15][16] In late 1936, Motobu returned briefly to Okinawa again and attended a roundtable discussion of karate masters in Naha on October 25.

He learned kakidi (kakede in Japanese), an ancient form of kumite from Sakuma and Kōsaku Matsumora, and it is practiced at Motobu-ryū to this day.