The　rapid　development　of　nanotechnology　offers　wide　prospects　for　the　application　of　nanomaterials　in　different　areas　of　industry,　technology　and　medicine.　Meanwhile,　the　biological　effect　and　safety　of　nanoparticles　have　attracted　worldwide　attention.　To　ensure　the　healthy　and　sustainable　development　of　nanotechnology,,　the　interaction　of　nanoparticles　with　organisms　and　the　biological　effect　produced　by　nanoparticles　can　not　be　neglected.　To　understand　the　biological　effects　of　nanoparticles,　investigating　how　the　nanoparticles　entrance　into　organisms　and　the　complicated　molecular　aspects　of　nano-bio　interactions　is　crucial.　The　main　routes　of　nanoparticles　entering　the　organisms　are　introduced.　The　interaction　of　nanoparticles　with　protein,　the　influencing　factors　and　characterization　of　the　interaction　are　reviewed　in　detail.　The　effects　of　nano-protein　interaction　on　the　structure　and　function　of　protein　and　the　biological　impact　of　nanoparticles　are　summarized.