Date Tadamune (伊達忠宗, DAH-tay; 23 January 1600 – 10 August 1658) was an early Edo period Japanese samurai, and the second daimyō of the 625,000 koku Sendai Domain in the Tōhoku region of northern Japan.

Although he was the second son, his elder half-brother Date Hidemune was born by Lady Iisaka, a concubine, and was thus not eligible to rule.

On Masamune's death in June 1636, he became daimyō, and entered Aoba Castle in Sendai for the first time in August of the same year.

He immediately took over the reins of government by replacing two of the six bugyōs, and re-establishing a multi-person system of magistrates and inspectors to provide more oversight and to eliminate corruption and arbitrary rule.

In terms of finances, from 1640 to 1643 he ordered a complete re-survey of the domain, bringing units of measurements in line with the nation-wide standards used by the Tokugawa shogunate.