Mahendra Sūri (c. 1340 – 1400) is the 14th century Jain astronomer who wrote the Yantraraja, the first Indian treatise on the astrolabe. He was trained by Madana Sūri, and was teacher to Malayendu Sūri. Jainism had a strong influence on mathematics particularly in the last couple of centuries BC. By the time of Mahendra Suri, however, Jainism had lost support as a national religion and was much less vigorous.