This　paper　presents　experimental　results　of　RPCs　performances　with　different　working　gas　mixtures.　Owing　to　Freon＇s　high　global　warming　potential,　its　threat　to　RPCs　aging　and　its　large　consumption　in　large　particle　physics　experiments,　studies　to　minimize　the　concentration　of　HFC-134A,　and　even　its　complete　replacement,　have　been　undertaken.　In　addition,　the　reduction　of　iso-butane　is　also　a　favorable　strategy,　due　to　the　flammability　level　of　the　gas　mixture.　Freon-less　working　gas　mixture　of　Ar/HFC-134A/i-C4H10/CO2=20/0/8/72　was　chosen　with　plateau　efficiency　of　86.3%　and　noise　rate　of　0.61　Hz/cm(2).　For　working　gas　with　lower　ratio　of　Freon,　Ar/HFC-134A/i-C4H10/CO2=20/20/8/52　was　suggested　with　plateau　efficiency　of　91.0%　and　noise　rate　of　0.19　Hz/cm(2),　in　which　Freon　was　decreased　by　22%　compared　to　the　BESIII　RPC　gas　mixture.　Furthermore,　iso-butane　was　decreased　to　6%　with　RPC＇s　efficiency　of　90%　and　noise　rate　of　0.20　Hz/cm(2)　achieved.　Finally,　the　explanation　of　RPC＇s　different　performances　at　various　working　gas　mixtures　has　been　validated　by　the　investigation　of　secondary　streamers.　This　study　will　be　helpful　for　RPC＇s　application　in　future　large　particle　physics　experiments,　in　which　RPCs　can　run　in　streamer　mode.