Atomically thin two-dimensional boron nitride nanosheets have spawned futuristic advancements in the arena of nanocatalysis research through their intriguing capability to act as exceptional support matrixes. Motivated by their phenomenal attributes, we have fabricated a magnetic boron nitride nanosheet-based cobalt catalytic system wherein boron nitride nanosheets are initially integrated with magnetic Fe 3 O 4 nanoparticles (NPs), and the resulting nanostructure is further surface-engineered with cobalt NPs to yield an h-BN/Fe 3 O 4 /Co hybrid. For gaining an insight into their structural and morphological features, reliable spectroscopic and microscopic characterization techniques including TEM, SEM, XRD, FT-IR, VSM, ED-XRF, XPS, BET, TGA, and AAS were employed. The developed nanohybrid material was then utilized to provide ready access to a library of highly bioactive 3,4-dihydropyrimidin-2(1H)-ones/thiones under ambient conditions. A plausible mechanistic route for furnishing 3,4dihydropyrimidin-2(1H)-ones catalyzed by h-BN/Fe 3 O 4 /Co has also been delineated. Ambient reaction conditions, solvent-free conditions, high product yield, and excellent thermal and mechanical stability of the catalyst along with facile magnetic retrievability and efficient recyclability are some of the phenomenal characteristics of this methodology. The present protocol besides exhibiting a wider functional group tolerance and a high turnover number was devoid of any additive, thus making it superior to literature precedents reported to date. In consideration of the striking catalytic activity of the h-BN/Fe 3 O 4 /Co nanomaterial, it can be anticipated that the present catalyst can not only possess a stupendous potential to expedite substantial manufacturing of other industrially demanding organic motifs but may also unlock insights for designing next-generation 2D catalytic materials.