In　this　paper,　based　on　the　weight　in　motion　(WIM)　system,　a　810　meters　long　rigid-frame　bridge　with　spans　arrangement　of　(145+260+260+145)　m　in　the　national　highway　G15　was　taken　as　the　background,　and　the　actual　vehicle　load　model　was　studied.　Firstly,　the　installation　and　debugging　of　the　WIM　system　was　briefly　introduced.　Secondly,　the　vehicle　load　statistical　distribution　features　were　obtained　using　acquisition　data.　Finally,　the　structure　response　in　action　of　actual　vehicle　load　and　vehicle　load　allowed　in　design　code　was　compared.　The　results　show　as　follows:　(1)　Gaussian　function　is　suitable　for　the　multi-peak　distribution　of　the　vehicle　weight　of　each　lane　in　both　the　general　traffic　state　and　the　dense　traffic　state.　(2)　At　present,　the　actual　vehicle　load　of　the　bridge　does　not　exceed　that　specified　in　design　code.