In　this　paper,　an　integrated　vapor　injection　compression　heat　pump　system　using　R1234yf,　R32,　R410A,　R22,　and　R134a　as　working　fluids　was　developed,　and　their　heating　performances　under　low　ambient　temperature　were　quantitatively　evaluated.　An　experimental　bench　was　built　to　test　the　system＇s　working　performance.　The　condensing　temperature,　evaporating　temperature,　power　input,　and　other　variables　were　analyzed　to　evaluate　the　system＇s　heating　capability　and　energy　efficiency.　Test　results　showed　that　the　R1234yf　system　can　run　at　the　evaporating　temperature　of　-20　degrees　C,　but　its　heating　coefficient　of　performance　was　5%　lower　than　R134a.　The　R1234yf　vapor　injection　system　provided　very　significant　performance　improvements　for　heating　performance　compared　with　no　vapor　injection:　the　heating　capacity　and　heating　coefficient　of　performance　can　be　improved　by　14.3%　and　11.7%,　respectively.