The development of functionalized magnetic nanoparticlesMagnetic Nanoparticles (MNPs)(FMNsFunctionalized Magnetic Nanomaterials (FMNs)) possessing different catalytically active sites represents an important field of green chemistry. One of the most attractive features of using FMNsFunctionalized Magnetic Nanomaterials (FMNs) as nanocatalystNanocatalysts is their easy magnetic separationMagnetic separation. Magnetic separationMagnetic separation involves the easy recovery and reusabilityReusability of catalysts, fewer usage of solvents and auxiliary chemicals, less energy, and reduces catalyst waste. Magnetic nanoparticlesMagnetic Nanoparticles (MNPs) are functionalized with different groups, such as silica, carbon, polymer, etc. to avoid agglomeration, which is one of the serious problems associated with uncoated nanoparticlesNanoparticles. To enhance the catalytic efficiency of these magnetic nanoparticlesMagnetic Nanoparticles (MNPs), many active species can be immobilized over the FMNsFunctionalized Magnetic Nanomaterials (FMNs). The exceptional fusion of superparamagnetic nanoparticlesSuperparamagnetic nanoparticles with specific catalytically active species offers the opportunity to resolve an issue related to the recovery of catalysts without any filtration technique. This chapter focuses on recent advances in green catalytic approaches using FMNsFunctionalized Magnetic Nanomaterials (FMNs) as nanocatalystsNanocatalysts. Recent scientific breakthrough on the preparation of different FMNsFunctionalized Magnetic Nanomaterials (FMNs) and their catalytic efficiency for various valuable transformations were discussed.