This　work　presents　a　complete　review　of　the　literature　on　and　a　critical　evaluation　and　thermodynamic　optimization　of　the　Li-Se　and　Na-Se　binary　systems.　The　modified　quasi-chemical　model　in　the　pair　approximation　(MQMPA)　was　employed　to　describe　the　liquid　solution　exhibiting　a　high　degree　of　short-range　ordering　behavior　of　atoms.　The　thermodynamic　properties　of　the　compounds　Li2Se　(cF12_Fm　(3)　over　barm),　Na2Se　(cF12_Fm　(3)　over　barm),　NaSe　(hP8_P6(3)/mmc),　and　NaSe2　(tI48_I　(4)　over　bar　2d)　were　also　calculated　by　using　first-principles　density　functional　theory　(DFT)　calculations　to　assist　the　thermodynamic　description　of　these　two　binary　systems.　All　the　available　and　reliable　experimental　data　are　reproduced　within　experimental　error　limits.　Moreover,　the　phase　equilibria　of　these　two　systems　at　low　total　pressure　were　analyzed　by　using　the　developed　thermodynamic　model.