The　position　error　of　column　type　strain　gauge　force　transducer　was　analysed,　and　the　effect　of　load　pad　on　the　position　error　was　investigated.　Six　load　pads　with　various　spherical　radius　were　designed　and　fixed　on　two　column　type　transducers　with　capacities　of　300　kN　and　100　kN　to　measure　their　position　errors　and　verify　the　theory　analysis.　It　is　shown　that　the　position　error　formula　could　be　used　to　illustrate　the　effect　of　load　pad　shape　on　the　position　error.　The　increment　of　spherical　radius　of　ball　or　cup　caused　the　increment　of　side　force　and　additional　moment　acted　on　the　force　transducer,　which　resulted　in　larger　position　error.　The　radius　should　be　as　small　as　possible　under　the　permission　of　material　strength.　©　2018　Web　Portal　IOP.　All　rights　reserved.