[Objective] The aim of this study was to extract RNA,DNA and protein from plants by using modified one step method.[Method]CTAB was used for the modifying of Biozol-based one step extraction method,which was then used for the isolation of RNA,DNA and protein from the roots of maize(Zea mays L.),soybean(Glycine max L.),alfalfa(Medicago sativa L.)and cucumber(Cucumis sativus L.).And the heme oxygenase-1 gene(HO-1)and calcium-dependent protein kinase-1 gene(CDPK1),as well as HO-1 protein were identified.[Result]The result of UV spectrophotometer determination and agarose gel electrophoresis analysis showed that the purity of obtained RNA and DNA sample was relatively high;HO-1 and CDPK1 gene exhibited the positive signals checked by RT-PCR;the extracted protein could be used for western blotting analysis;the whole isolation procedure cost 3 h.[Conclusion]This method can be used as a good reference for researcher and will offer a better value with a wide range of applications.