Comprehending the soil organic carbon (SOC)-aggregate-enzyme dynamics following conversion of barren land to grassland is imperative in ecologically sensitive semi-arid regions. The objective of the study was to scrutinise the effects of grasses on soil aggregate stability, SOC pools, and functional diversity. We set up sample plots of six perennial grasses, namely, Cenchrus ciliaris L. (Ccil), Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L. Jacobs. (Pmax), Chrysopogon fulvus (Spreng.) Chiov. (Cful), Heteropogon contortus (L.) P. Beauv. ex Roem. & Schult. (Hcon), Sehima nervosa (Rottler) Stapf (Sner), and Vetiveria zizanioides (L.) Nash. (Vziz). The root properties of grasses and their decay kinetics, aggregate size distribution, and stability, SOC in bulk soil and aggregates, as well as enzyme activity, were measured. The decay rate of Ccil root was the highest. Grasses significantly impacted soil aggregate distribution, stability, and carbon preservation capacity at 0-30 cm depths. Compared with unconverted fallow land (UFL), the mass of large macroaggregates increased by similar to 1.9-4.2- and 4.4-11-fold at 0-15 and 16-30 cm soil layers, respectively, whereas the sand-free mean weight diameter was 24-69 % and 21-90 % greater in those layers, respectively. However, the masses of microaggregates and silt+clay significantly declined after grass establishment. The Ccil, Hcon, and Sner significantly increased the SOC stock at 0-30 cm depth by 86, 26, and 76 %. The small macroaggregates contributed significantly to carbon preservation, protecting 50 % SOC under Ccil, Hcon, and Sner at 0-30 cm. The activities of soil enzymes were significantly higher under Ccil than other grasses and UFL. Hence, Cenchrus ciliaris L., Heteropogon contortus (L.) P. Beauv. ex Roem. & Schult., and Sehima nervosa (Rottler) Stapf could be recommended for land restoration in the semi-arid agroecology of India for their superior capacity to improve carbon sequestration, soil aggregation, and microbial activity.