Nanoparticles（NPs） have potential application in the field of biomedicine due to their unusual physicochemical，optical，and antibacterial properties. However，as particle size decreases，small size particles show increased toxicity. Meanwhile，their biosafety have attracted the attention of researchers. NPs interact with mammalian cells，and they can interfere with subcellular components，such as nuclei，mitochondria，endoplasmic reticulum and lysosomes，then causing apoptosis or necrosis. This brief review tries to summarize the toxicity effect of NPs on subcellular level，combining with the characteristics NPs.