The　objective　of　the　paper　is　to　develop　a　group　of　models　of　operating　speed　of　free-flow　passenger　cars　on　freeway.　The　paper　analyzed　the　driver＇s　process　of　collecting　and　dealing　with　information　in　details.　Based　on　a　amount　of　field　data,　factors　that　influenced　speed　and　corresponding　rules　of　operating　speed　were　definitely　explored　in　this　paper.　A　group　of　models　used　statistical　methods　were　developed　for　prediction　of　operating　speed　of　different　alignments　with　design　consistency　concept.　Compared　with　the　result　of　field　data,　these　models　have　the　merit　of　high　prediction　accuracy　of　the　85th-percentile　operating　speed.　The　model　could　be　applied　widely　in　the　alignment　design　approach　of　operating　speed　and　traffic　simulation.　Finally,　the　paper　had　drawn　a　speed-profile　of　a　freeway　with　these　models.　Thus　designers　and　traffic　engineers　could　diagnose　and　reduce　inconsistency　in　design　and　ensure　that　most　drivers　would　be　able　to　operate　safety　at　their　speed　along　the　entire　alignments.　This　have　settled　good　foundation　for　utilizing　operating　speed　to　rate　design　consistency.　At　the　same　time,　it　provides　data　support　for　geometric　designer　and　researchers　to　use　the　operating　speed　concept　and　to　establish　the　operating　speed　design　criterion　of　highway　in　China.