Cecil Mallaby Firth (1878 – 1931) was a British Egyptologist.
Firth worked in Nubia of 1907 to 1911, then it started to explore the complex of Djoser's Step Pyramid in Saqqara where, in 1924, he discovered the serdab of the pharaoh, which is now in the Egyptian Museum in Cairo.
Firth then worked in collaboration with James E. Quibell and subsequently with Jean-Philippe Lauer on his arrival on the site in 1926.
He was named inspector of the area of Saqqara in 1927 by the Antiquities Services.
In 1928 and 1929, Firth began the opening of the funerary complex of Userkaf, the first king of the 5th dynasty, and that of a small pyramid located just at the south, allotted to his queen.