Ensuring　the　security　of　data　outsourced　to　cloud　is　a　prerequisite　for　the　application　of　Internet　of　Things　(IoT)　in　actual　production.　Secure　search　based　on　homomorphic　encryption　can　provide　high　security　and　require　no　expensive　setup　procedure,　which　can　be　applied　to　resource-limited　devices　in　IoT.　However,　the　existing　schemes　usually　have　poor　search　performance　and　do　not　consider　multi-owner　setting.　To　solve　these　issues,　we　propose　an　efficient　homomorphic　encryption-based　secure　search　scheme　in　multi-owner　setting.　Specifically,　we　construct　a　secure　search　protocol　based　on　multi-key　homomorphic　encryption,　which　can　be　deployed　in　multi-owner　setting.　Meanwhile,　we　improve　the　efficiency　of　our　scheme　by　optimizing　the　search　algorithm.　Formal　security　analysis　proves　that　our　scheme　is　secure　against　chosen　plaintext　attack,　and　extensive　experiments　demonstrate　that　our　scheme　improves　the　search　efficiency　by　1000x　when　compared　with　state-of-the-art　solutions.　　©　2014　IEEE.