Hyrum Mack Smith (March 21, 1872 – January 23, 1918) was a member of the Quorum of the Twelve Apostles of the Church of Jesus Christ of Latter-day Saints (LDS Church). Smith was born in Salt Lake City, Utah Territory, the eldest son of church apostle and future church president Joseph F. Smith and Edna Lambson. Smith was named after his paternal grandfather Hyrum Smith, who was the elder brother of LDS Church founder Joseph Smith and a prominent leader of the early church. After returning from his mission, Smith worked at ZCMI while also serving as a part-time missionary in Salt Lake City.