This　study　is　mainly　aimed　at　aircraft　propeller　blades.　In　this　paper,　a　propeller　blade　model　is　established　by　ANSYS　software,　and　its　vibration　characteristics　are　studied　by　fluid–structure　coupling　simulation　and　modal　analysis.　In　modal　analysis,　the　ordinary　modal　analysis　was　carried　out　on　the　steel　blade.　The　softening　effect　caused　by　the　change　of　blade　speed　is　also　studied.　Modal　analysis　shows　that　rotational　softening　reduces　blade　stiffness　and　natural　frequencies.　Aerodynamic　force　and　centrifugal　force　are　introduced　to　conduct　fluid–structure　coupling　simulation　and　prestressed　modal　analysis　of　the　blades,　and　study　the　influence　of　these　forces　on　the　modal　frequency　of　the　blades.　After　centrifugal　force　loading,　the　first　natural　frequency　increases　significantly.　With　the　change　of　blade　speed,　the　frequency　of　each　order　of　blade　also　has　different　changes.　The　natural　frequencies　of　each　order　of　forward　precession　increase　with　the　increase　of　blade　speed,　and　the　natural　frequencies　of　each　order　of　reverse　precession　decrease　with　the　increase　of　blade　speed.　The　first-order　mode　critical　speed　of　the　rotating　blade　increases,　and　the　second-order　mode　speed　decreases.　After　aerodynamic　loading,　the　frequencies　of　the　blades　do　not　change　much,　and　the　critical　velocities　of　the　first　and　second　order　modes　of　the　rotating　blades　increase.　©　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.　2024.