The　Risley-prism　system　has　a　great　application　prospect　in　target　tracking　with　the　aim　of　both　large　field　of　view　and　high　precision　due　to　its　extension　of　the　field　of　view.　Although　increasing　the　prism　vertex　angle　enlarges　the　magnification　of　the　field　of　view,　it　also　expands　the　influence　of　the　system　assembly　error　on　the　target　pointing　accuracy.　Considering　the　low　pointing　accuracy　of　the　Risley-prism　system　with　a　large　vertex　angle,　this　paper　proposes　a　method　of　correcting　the　pointing　error　of　the　Risley-prism　system　based　on　the　particle　swarm　algorithm.　A　Risley-prism　imaging　system　is　built　with　a　prism　vertex　angle　of　14.85°　and　a　prism　refractive　index　of　1.515.　A　mathematical　model　of　an　experimental　prototype　based　on　assembly　error　analysis　is　built　by　using　pointing　test　results　of　the　ideal　model.　Parameter　identification　of　the　setting　values　of　the　prism　vertex　angle　and　the　prism　refractive　index　in　the　reverse　solution　algorithm　is　conducted.　Finally,　a　pointing　test　is　carried　out　on　the　experimental　prototype.　The　experimental　results　demonstrate　that　the　proposed　method　effectively　improves　the　pointing　accuracy　of　the　Risley-prism　system　with　a　large　prism　vertex　angle.　When　the　method　is　applied,　the　maximum　pointing　error　decreases　by　52.4%,　and　the　average　pointing　error　reduces　by　43.3%.　The　root-mean-square　error　decreases　by　44.0%,　and　the　fitting　radius　of　the　least　squares　method　decreases　by　44.7%.　©　2021,　Chinese　Lasers　Press.　All　right　reserved.