In the current project, we describe a green, simple, and eco-friendly procedure for the oxidation of aromatic alcohols into benzaldehydes derivatives with a new Fe3O4@CS@γ-Al2O3 nanocomposite and H2O2 as the sole oxidant for the first time. The catalytic performance of Fe3O4@CS@γ-Al2O3 composites as heterogeneous nanocatalysts were studied in the selectively oxidized benzyl alcohols to generate relevant benzaldehyde. Also, the functional parameters of the reaction, containing H2O2 concentration, time, different solvents, and nanocatalyst dosage, were investigated. XRD, FTIR, EDX, FESEM, and VSM analyses were applicated to confirm the size of morphology and structure of the prepared samples. Easy separation, excellent conversion, good recoverability, magnetic catalyst separation, low time, excellent function, and ultrasound irradiation can be named as some highlighting features of this project.