Thutmose III, (died 1426 BCE), king (reigned 1479–26 BCE) of the 18th dynasty, often regarded as the greatest of the rulers of ancient Egypt. Thutmose III was a skilled warrior who brought the Egyptian empire to the zenith of its power by conquering all of Syria, crossing the Euphrates (see Tigris-Euphrates river system) to defeat the Mitannians, and penetrating south along the Nile River to Napata in Sudan. He also built a great number of temples and monuments to commemorate his deeds.

Thutmose III was the sixth pharaoh of the Eighteenth Dynasty. Officially, Thutmose III ruled Egypt for almost 54 years and his reign is usually dated from 28 April 1479 BC to 11 March 1425 BC, from the age of two and until his death at age fifty-six; however, during the first 22 years of his reign, he was coregent with his stepmother and aunt, Hatshepsut, who was named the pharaoh. While he was shown first on surviving monuments, both were assigned the usual royal names and insignia and neither is given any obvious seniority over the other. Thutmose served as the head of Hatshepsut's armies. During the final two years of his reign, he appointed his son and successor, Amenhotep II, as his junior co-regent. His firstborn son and heir to the throne, Amenemhat, predeceased Thutmose III.

Becoming the sole ruling pharaoh of the kingdom after the deaths of Thutmose II and Hatshepsut, he created the largest empire Egypt had ever seen; no fewer than 17 campaigns were conducted and he conquered lands from the Niya Kingdom in northern Syria to the Fourth Cataract of the Nile in Nubia.

When Thutmose III died, he was buried in the Valley of the Kings, as were the rest of the kings from this period in Egypt.