What Asian admiral sailed to Sri Lanka and ports along the Persian Gulf in 1400s?

The Asian admiral you're likely thinking of is Zheng He, a Chinese Muslim explorer and diplomat who lived during the Ming dynasty.

While he didn't specifically sail to Sri Lanka, he did visit ports in the Indian Ocean, including those along the Persian Gulf, during his seven voyages between 1405 and 1433. He led massive fleets of ships and his expeditions were some of the largest and most impressive naval voyages in human history.

Although there's no concrete evidence of Zheng He reaching Sri Lanka, his vast expeditions covered a huge geographical area, including parts of Southeast Asia, India, and the Persian Gulf.

Therefore, while he might not have directly sailed to Sri Lanka, his voyages during the 1400s were highly significant and explored much of the Asian and African coastline.