To　improve　the　seismic　performance　of　steel　column　splicing　flange　joints,　different　weld　details　between　the　column　and　the　flange　plate　were　proposed　in　this　study,　and　four　full-scale　specimens　were　designed　and　tested　under　cyclic　loads.　Finite　element　analysis　was　conducted　to　further　check　the　joint　performances　and　the　weld　behaviors.　The　hysteresis　behaviors,　yield　moment,　ductility,　bolt　forces,　energy　dissipation,　stress　and　strains　were　analyzed.　The　parametric　analysis,　with　finite　element　models　validated　by　test　results,　was　conducted,　discussing　the　influences　of　the　weld　details,　weld　geometries　and　flange　openings.　According　to　the　results,　three　of　the　four　different　weld　details　developed　different　advantages　on　ductility　or　energy　dissipation　capacity,　bolt　tension　distribution,　stress　or　strain　distributions.　Larger　weld　leg　size　would　increase　the　resistance　of　the　bolted　flange　splice　joint,　but　may　also　cause　weld　residual　stress　and　prying　force.　The　reduction　of　flange　opening　can　improve　the　stiffness　and　yield　moments　of　the　Type　B　flange　joints.　Formulas　for　the　yield　moments　of　the　joints　with　recommended　weld　types　were　proposed　and　validated　by　both　test　and　numerical　analysis　results,　and　additional　formulas　to　check　weld　details　were　proposed　for　seismic　design　of　bolted　flange　joints　in　prefabricated　steel　structures.