Andrew Belcher Gray (July 6, 1820 – April 16, 1862) was an American surveyor and mapmaker. Originally from Norfolk, Virginia, Gray studied engineering and surveying with the U.S. army under Andrew Talcott and was a part of the team that helped him survey the Mississippi Delta in 1839.
Gray later joined the Texas Navy and was part of the efforts to create an independent Republic of Texas. After the absorption of Texas into the United States, Gray became a surveyor for the new boundary commission. He also served as chief surveyor for the U.S.–Mexican commission, establishing the border after the Treaty of Guadalupe Hidalgo. When John Bartlett, the U. S. Commissioner, gave away the important Mesilla Valley because of a cartographic error, Gray opposed the deal vigorously and was therefore fired from the commission.
Gray nevertheless landed on his feet. By the early 1850s, the Texas Western Railroad engaged him to survey the region between San Antonio and the Colorado River. When the Civil War broke out, Gray quickly joined the Confederate Army as an engineer. In 1862 he was killed when the boiler of a steamboat he was traveling on exploded.
