This　paper　investigates　the　influence　of　recycled　fine　aggregates　(RFA)　on　RFA　concrete　through　a　mesoscale　approach,　mainly　focusing　on　mechanical　properties　and　frost　resistance.　First,　considering　the　higher　water　absorption　and　weaker　mechanical　performance　of　RFA,　the　original　Rigid　Body　Spring　Model　(RBSM)　for　normal　concrete　was　modified　according　to　various　collected　experimental　parameters,　including　porosity,　pore　size　distribution,　and　basic　mechanical　parameters.　Then,　the　modified　model　was　applied　to　analyze　frost　damage　behaviors　of　RFA　concrete　and　verified　with　experimental　data.　Furthermore,　the　verified　model　was　extended　to　a　wider　range　of　influential　factors,　such　as　RFA　replacement　ratio,　water　-to　-cement　ratio,　and　water　absorption　ratio　of　RFA,　to　obtain　a　general　and　quantitative　evaluation　of　frost　resistance　for　RFA　concrete.　Finally,　a　probabilistic　damage　model　based　on　a　two　-parameter　Weibull　distribution　was　constructed　to　establish　a　relationship　between　the　life　(i.e.,　the　number　of　freezing　-thawing　cycles)　and　key　parameters　(RFA　replacement　ratio,　water　-to　-cement　ratio,　and　water　absorption　of　RFA).　It　is　both　shown　in　the　experiment　and　simulation　that　the　frost　resistance　of　RFA　concrete　decreases　significantly　as　the　RFA　replacement　ratio　and　RFA　water　absorption　ratio　increase,　and　the　water　absorption　of　RFA　has　a　significant　effect　on　the　performance　of　RFA　concrete　under　FTCs.