Taking　composite　girders　with　corrugated　steel　webs　and　concrete-filled　steel　tubular　(CSW-CFST)　truss　chords　as　the　research　object,　the　torsional　behavior　tests　and　theoretical　analysis　on　the　composite　girders　were　conducted,　in　comparison　with　those　of　composite　girders　with　corrugated　steel　webs　and　circular　hollow　section　(CSW-CHS)　truss　chords　and　composite　box　girders　with　CSW-CFST　chords.　The　twist　failure　mode,　the　sectional　form,　and　the　influence　of　the　concrete　in　chord　on　the　torsional　behavior　of　composite　girders　above　were　studied.　Furthermore,　the　calculation　method　for　the　torsional　bearing　capacity　of　composite　girders　was　discussed.　Results　show　that　the　cross　section　of　composite　girders　with　CSW-CFST　truss　chords　can　be　equivalent　to　the　closed　box　cross　section.　The　twist　failure　mode　is　that　the　concrete　bridge　deck　slab　cracks　obliquely　along　the　direction　of　45◦　with　respect　to　the　axis　of　composite　girders,　accompanied　with　the　yielding　longitudinal　rebar.　The　concrete　in　chord　contributes　to　the　torsional　stiffness　and　bearing　capacity　of　composite　girders　to　some　extent.　Based　on　the　linear　superposition　method　of　the　stiffness,　the　calculation　method　for　the　composite　torsional　stiffness　of　CFST　specimen　is　established.　For　the　four　twist　failure　modes　possibly　occurring　in　composite　girders　with　CSW-CFST　truss　chords,　the　calculation　method　for　the　torsional　bearing　capacity　was　put　forward.　Moreover,　the　deviation　between　the　results　from　the　calculation　method　for　the　torsional　bearing　capacity　put　forward　in　the　present　study　and　those　from　the　tests　and　finite　element　analysis　is　not　more　than　8.　5%.　©　2023　Editorial　Office　of　China　Civil　Engineering　Journal.　All　rights　reserved.