Thin films of AgInSe₂ ternary compound were grown by a successive process in which the production of AIS-Ag–AIS-Ag–AIS-Ag layers was deposited by e-beam and thermal evaporation on p-type silicon substrates. The formation of a stoichiometric AgInSe₂ thin film with 75.2% crystallinity was achieved and the film had homogenous and smooth surfaces. n-AgInSe₂/p-Si structure has exhibited good rectifying behavior with rectification ratio of 3.99 × 10³. The ideality factor and saturation current were found to be 1.74 and 2.71 × 10⁻⁷ A, respectively. The n-AgInSe₂/p-Si heterojunction diode exhibited non-ideal reverse-bias capacitance–voltage (C ⁻²–V) characteristic due to fully depletion of n-AgInSe₂ side. The basic photovoltaic parameters of the diode such as open-circuit voltage (V _oc), short-circuit current (I _sc), and fill factor (FF) were obtained as 0.49 V, 4.03 mA, and 27.65%, respectively.