Samuel Theobald (November 12, 1846 – December 30, 1930) was a clinical professor of ophthalmology and otology at Johns Hopkins University Medical School.

The elder Theobald was a medical doctor, as was Samuel's older brother, Elisha Warfield Jr. (see Smith-Theobald Family).

Theobald's father died in 1851 so he was largely raised in the home of his grandfather, the surgeon Nathan Ryno Smith.

Theobald became emeritus in 1925, the same year that the Wilmer Ophthalmological Institute was founded at Johns Hopkins.

Around the time he completed his medical degree, Theobald married Caroline Dexter DeWolf (1848–1929).