Maria Emma Gray (1787–9 December 1876), was an English conchologist, algologist and scientific illustrator. Gray was born in 1787 at Greenwich Hospital. She married in 1810 Francis Edward Gray, who died four years later, and had by him two daughters, who survived her. Both daughters, Emma Juliana Gray Smith and Sophia Elizabeth Gray Stokes, were also scientific illustrators. In 1826 she married his second cousin, John Edward Gray. She greatly assisted her second husband in his scientific work, especially by her drawings. Between 1842 and 1874 she published privately five volumes of etchings, entitled Figures of Molluscan Animals for the use of Students, and she mounted and arranged most of the Cuming collection of shells in the British Museum.