Measuring　the　interaction　between　cities　is　an　important　research　topic　in　many　disciplines,　such　as　sociology,　geography,　economics,　and　transportation　science.　The　traditional　and　most　widely　used　spatial　interaction　model　is　the　gravity　model,　but　it　requires　the　parameters　to　be　artificially　set.　In　this　paper,　we　propose　a　parameter-free　interactive　city　choice　(ICC)　model　that　measures　intercity　interaction　from　the　perspective　of　individual　choice　behavior.　The　ICC　model　assumes　that　the　probability　of　an　individual　choosing　to　interact　with　a　city　is　proportional　to　the　number　of　opportunities　in　the　destination　city　and　inversely　proportional　to　the　number　of　intervening　opportunities　between　the　origin　city　and　the　destination　city,　calculated　using　the　travel　time　in　the　transportation　network.　The　intercity　interaction　intensity　can　be　obtained　by　calculating　the　product　of　this　probability　and　the　origin　city＇s　population.　We　apply　the　ICC　model　to　measure　the　interaction　intensity　among　339　cities　in　China　and　analyze　the　impact　of　changes　in　the　Chinese　land　transportation　network　from　2005　to　2018　on　the　intercity　and　city　interaction　intensity.　The　results　show　that　our　model　provides　an　alternative　method　for　measuring　the　intercity　interaction.