The present application provides an electrolyte for lithium ion battery which comprising a mixture of organic solvents consisting of ethylene carbonate, ethyl methyl carbonate, dimethyl carbonate and carboxylate ester, wherein a mass ratio of ethylene carbonate, ethyl methyl carbonate, dimethyl carbonate and carboxylate ester is (20%-30%):(45%-55%):(10%-20%):(5%-15%); a mixture of additives consisting of vinylene carbonate, propane sultone, fluorinated ethylene carbonate and perfluorohexylsulfonyl fluoride; and a lithium salt. The electrolyte for lithium ion battery provided according to the present application has good wettability and high absorption rate. The present application also provides a lithium ion battery with high energy density, small internal resistance, good cycle performance and good charge and discharge performance.