Olof Celsius (the elder) (19 July 1670 – 24 June 1756) was a Swedish botanist, philologist and clergyman, He was a professor at Uppsala University, Sweden. Celsius was a mentor of the botanist and scientist Carl Linnaeus. Celsius wrote his most famous book on biblical plants, Hierobotanicon, in 1745–47. Celsius was also a prominent runologist. Olof Celsius was made a member of the Royal Swedish Academy of Sciences in 1739. The standard author abbreviation Celsius is used to indicate this person as the author when citing a botanical name.