In　this　paper,　an　anti-oxidation　film　was　formed　on　the　surface　of　Sn3.0Ag0.5Cu　solder　balls　by　using　a　composite　system　of　benzotriazole　(BTA)　and　2-aminobenzimidazole　(2-ABT).　The　properties　of　anti-oxidation　film　were　measured　by　shaking　balls　test,　shearing　strength　test　and　cavity　test.　The　results　showed　that　when　the　combination　of　1.5　g/L　BTA　and　0.5　g/L　2-ABT　was　used　to　form　an　anti-oxidation　film　on　the　surface　of　solder　balls,　the　life　of　the　solder　balls　surface　without　dendrite　wear　during　shaking　balls　test　was　increased　by　10　times,　and　the　cavity　rate　was　decreased　from　5　%　to　3　%,　resulting　in　that　the　shear　strength　of　the　solder　joint　was　increased　from　20.96　MPa　to　40.45　MPa.　And　the　theoretical　calculation　results　showed　that　N2　atoms　of　benzotriazole　and　2-aminobenzimidazole　molecules　were　the　most　active　and　adsorbed　on　the　surface　of　the　solder　balls　to　form　anti-oxidation　films.