A Be2C monolayer, as a new direct band gap semiconductor, has good potential for use in optoelectronic applications. In this article, the effects of different biaxial stresses and strains on the electronic and optical properties of a Be2C monolayer are investigated via first-principles calculations in the frame work of the density functional theory. The study of the electronic properties indicates that under biaxial strains, the direct band gap of the Be2C monolayer becomes indirect (K -> I), while under stress, it remains direct. In addition, the energy gap increases under strain, While it decreases under stress conditions. The optical calculations show that strain and stress effects cause red and blue shifts, respectively, in the optical spectra. Furthermore, the low values of reflectivity and absorption in the low energy ranges indicate the transparency of this monolayer. These results can be used in the fabrication of future nanoelectronic systems. (C) 2016 Elsevier Ltd. All rights reserved.