The Myinsaing Kingdom (Burmese: မြင်စိုင်းခေတ် [mjɪ̀ɴzáɪɴ kʰɪʔ]) was the kingdom that ruled central Burma (Myanmar) from 1297 to 1313. Co-founded by three brothers from Myinsaing, it was one of many small kingdoms that emerged following the collapse of Pagan Empire in 1287. Myinsaing successfully fended off the second Mongol invasion in 1300–01, and went on to unify central Burma from Tagaung in the north to Prome (Pyay) in the south. The brothers' co-rule ended between 1310 and 1313, with the death of the two elder brothers. In 1315, the central Burmese state split into two rival states of Pinya and Sagaing. Central Burma would not be reunified until the rise of Ava five decades later.

The origins of the Myinsaing period can be traced back to the late Pagan period. By the 1270s, the Pagan Dynasty, which had ruled the Irrawaddy valley and its periphery for over two centuries, was on its last legs. Between one and two-thirds of Upper Burma's cultivatable land had been donated to religion, and the crown had lost resources needed to retain the loyalty of courtiers and military servicemen. The beginning of the end of Pagan came in 1277 when the Mongol Empire first invaded northernmost Pagan territories (present-day Dehong and Baoshan prefectures, Yunnan). The Mongols proceeded to invade northern Burma in 1283–85, occupying down to Tagaung. King Narathihapate fled to Lower Burma. In the next two years, while the king negotiated a ceasefire and eventually a surrender with the Mongols, the defence of central Burma passed to the army led by three brothers named Athinkhaya, Yazathingyan and Thihathu from Myinsaing.

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