On-time　arrival　is　very　important　for　car　commuters.　What　is　the　minimum　acceptable　travel　speed　of　the　car　commuters　in　the　case　of　ensuring　on-time　arrival?　What＇s　the　on-time　arrival　probability　of　the　car　commuters　at　the　acceptable　travel　speed　based　on　the　current　urban　road　speed?　This　research　seeks　to　establish　a　simple,　effective,　and　trusty　acceptable　travel　speed　model　based　on　the　expectation　and　tolerance　of　the　car　commuters　for　urban　road　traffic.　And　a　travel　speed　reliability　model　of　car　commuters＇　congestion　tolerance　perception　was　established　based　on　actual　revealed　preference　survey　data　of　car　commuters.　The　results　illustrate　that　the　acceptable　travel　speed　is　equal　to　0.71　multiple　average　travel　speed,　their　value　of　correlation　coefficient　R2　is　0.96,　and　prediction　accuracy　of　the　acceptable　travel　speed　model　is　larger　than　75%.　The　analysis　results　of　three　months　of　road　section　speed　data　illustrate　that　the　on-time　arrival　probability　of　the　car　commuters　at　the　acceptable　travel　speed　is　larger　than　60%　in　Beijing　Jingtong　Expressway.　The　research　objectively　quantitatively　evaluates　the　congestion　tolerance　of　car　commuters　based　on　travel　speed　reliability.　It　opens　up　new　possibilities　for　urban　road　traffic　accurate　assessment　and　effective　operation　management　based　on　the　expectation　and　tolerance　of　travelers,　and　it　will　be　contributing　to　improving　and　enhancing　urban　road　traffic　operation　service　quality.　©　2021　IEEE.