This article presents a phytochemical study of the roots of Croton dybowskii Hutch. Colorimetric methods, UV-visible spectrophotometry and fractionation on a silica gel column were used for chemical analysis, the determination of total polyphenols and flavonoids. The chemical screening allowed us to highlight six chemical families out of the eight expected. These qualitative analyzes have shown that the Croton dybowskii species is rich in alkaloids, flavonoids, anthracene derivatives, terpenes, coumarins and saponosides. Quantitative analyzes, in particular, the contents of flavonoids and total polyphenols, gave results which vary according to the extraction solvent. The flavonoid contents are less significant for the aqueous extracts and significant for the hydroethanolic and ethanolic extracts, they vary between 0.4 ± 0.02 and 5.8 ± 0.1 mg EC/g DM) whereas those in polyphenolic compounds reveal a more significant concentration for hydro-ethanolic extracts followed by those of ethanolic and aqueous extracts, respectively; 15.2 ± 0.3; 3.6 ± 0.1 and 3.3 ± 0.2 mg EAG/gMS. This study also enables the production of 14 fractions after separation by chromatography on an open column and the isolation of a compound after purification on a Thin Layer Chromatography (TLC). The interest of the Croton dybowskii Hutch root could be justified by its richness in secondary metabolites.