In　order　to　explore　the　mental　retardation　of　patients　with　depression,　the　visual　search　paradigm　was　used　in　this　study.　The　emotional　expression　(happy,　sad)　and　neutral　expression　were　used　as　interdependent　or　search　targets　in　this　paradigm.　Subjects　were　asked　to　search　the　target　face　form　a　matrix　containing　16　emotional　faces　after　watching　the　target　face.　The　measurement　indices　of　the　search　process　-　scanpath　duration　(SPD),　scanpath　length　(SPL),　convex　hull　area　(CHA)　-　were　collected　and　analyzed.　The　three　indexes　of　patients　were　all　larger　than　those　in　control　group　and　there　were　significant　differences　between　the　groups.　It　can　be　seen　that　two　kinds　of　emotional　faces　reduce　the　search　efficiency　of　depression　patients　and　there　is　a　slow　response　and　mental　retardation　phenomenon　for　depression　in　the　search　process.　©　2017　IEEE.