In the current study camphor oil was investigated at the form of bulk and nanoemulsion to evaluate their toxic effect on cotton leafworm and Swiss albino mice. Camphor nanoemulsion (CamONPs) was characterized. GC-Mass spectroscopy showed that the main component of both bulk and nanoemulsion was Eucalyptol. Transmission Electron Microscopy showed that the size of CamONPs ranged between 18-36 nm. Fourier Transforms Infrared revealed distinct peaks at wavenumber 3350 and 1640 cm-1 where those peaks were disappeared in the bulk form. LC50 value of CamONPs on S. littoralis larvae was 1664 ppm, while of bulk emulsion was 20232 ppm. LD50 values of CamONPs and its bulk form on mice recorded 1.12 and 1.52g/kg b.w., respectively. Mice treated with LD10 of bulk camphor showed increase in WBC counts which slightly decreased in mice treated with CamONPs. RBC counts, Haemoglobin level and Hematocrit % were significantly changed in CamONPs treatment comparing to bulk form. MCV, MCH, MCHC and platelet counts showed alteration in both treatments comparing to untreated mice. Significant changes were noticed in liver tranceaminases, urea and creatinine. CamONPs revealed significant decrease against tumor markers (AFP, CEA) in comparison to its bulk form and both treatments showed significant changes comparing to control group.