Antimony selenide, Sb2Se3, has been attracted widespread attention in photovoltaic applications due to its high absorption coefficient and suitable band gap. However, the influence of uniaxial strain and electric field on the electronic and photovoltaic properties of multilayer Sb2Se3 is still unknown. Here, the quantitative relationship, such as strain-property, electric field-property, as well as thickness-property, is explored via first-principles calculations. Our results demonstrate that the band gap and photovoltaic parameters (Jsc, Voc, FF and PCE) of multilayer Sb2Se3 are not only affected by the uniaxial strain and electric field, but can also be tuned via the coupling of thickness with strain and electric field. The band-gap of multilayer Sb2Se3 is linear dependent on uniaxial strain and external electric field. We found that the effect of strain on the photovoltaic parameters could be negligible as compared with the effect of thickness. However, the effect of electric field is thickness dependent, 1 ‒ 2 layer(s) thin films are not affected while the impact of electric field increases with the increasing thickness. The quantitative strain (electric field)-properties relation of multilayer Sb2Se3 suggesting that Sb2Se3 films have a potential application in the field of strain and electric field sensors.