To　clarify　the　mechanism　of　optimal　pricing　for　public　off-street　parking　facilities　and　its　implementation　method,　this　paper　establishes　a　basic　model　and　an　extension　model　that　can　determine　the　optimal　price　for　parking　facilities　based　on　parking　permits.　In　the　basic　model,　firstly,　using　users＇　valuation　for　parking　permits,　we　establish　a　model　that　can　determine　their　optimal　allocation.　Next,　using　an　auction　mechanism　(e.g.,　ascending　proxy　agent　system),　we　obtain　the　optimal　price　for　each　parking　facility.　In　the　extension　model,　the　single　purchase　period　of　parking　permits　is　extended　to　multiple　purchase　periods.　Under　such　settings,　we　propose　an　evolutionary　method　to　achieve　the　optimal　price.　Finally,　through　a　numerical　experiment,　we　verify　the　feasibility　of　the　ascending　proxy　agent　system　for　optimal　pricing　and　the　validity　of　the　evolutionary　method　for　solving　the　extension　model.　The　results　reveal　the　following:　the　user　equilibrium　state　under　the　parking　permits　is　consistent　with　the　social　optimal　state;　we　obtain　the　optimal　allocation　and　prices　of　parking　permits　using　an　ascending　proxy　agent　system;　the　optimal　price　has　strategy-proofness　which　lets　the　users　report　their　valuation　truthfully;　compared　with　the　valuation　for　parking　permits,　the　variation　of　the　number　of　parking　spaces　is　more　sensitive　for　the　optimal　pricing;　multiple　purchase　periods　can　achieve　higher　social　welfare　than　that　of　single　purchase　period;　using　the　evolutionary　method,　we　obtain　the　optimal　allocation　of　parking　permits　and　optimal　prices　in　a　finite　number　of　iterations;　and　the　evolutionary　method　achieves　high　social　welfare　in　a　few　iterations.　©　2018,　Editorial　Department　of　China　Journal　of　Highway　and　Transport.　All　right　reserved.