Advanced　traveler　information　systems　(ATIS)　are　designed　to　assist　travelers　to　make　better　choices　and　improve　the　overall　performance　of　the　whole　transportation　system.　This　paper　proposes　a　CPT　(cumulative　prospect　theory)-based　network　equilibrium　model　to　re-evaluate　and　re-quantify　the　ATIS　benefit　with　the　assumption　of　endogenous　market　penetration.　Heterogeneous　travelers　are　considered　and　classified　into　several　classes　in　terms　of　their　reference　points,　and　the　ATIS　market　penetration　for　each　class　is　determined　by　the　reference　point　of　their　own.　Furthermore,　we　assume　that　travelers　equipped　with　ATIS　will　receive　the　complete　information　and　hence　make　route　choice　in　a　CPT-based　user　equilibrium　manner,　while　travelers　without　ATIS　will　make　route　choice　in　a　logit-based　stochastic　manner.　The　numerical　results　show　that　the　equipped　users　are　always　able　to　obtain　the　positive　benefit,　and　the　effect　of　the　provided　information　is　more　obvious　for　users　with　higher　reference　points　in　a　market　with　lower　travel　demand　and　market　penetration.　©　ASCE.