[Objective] The relative enzyme activity and kinetic parameters of typical forest soil in loess hilly region were analyzed and the driving factors of soil enzyme activity characteristics were revealed in order to provide theoretical basis for the construction and improvement of regional artificial forests. [Methods] Coniferous forest (Pinus tabulaeformis), broad-leaved forest (Quercus acutissima), and mixed forest (P. tabulaeformis Q. acutissima mixed forest) in loess hilly region were selected as the research objects. Through field soil sampling and laboratory incubation analysis, soil physical and chemical properties and specific soil carbon, nitrogen, phosphorus transformation-linked enzyme activities 〔β-1,4-Glucosidase (BG), N-acety-β-glucosaminidase (NAG)〕, L-leucine aminopeptidase (LAP), and alkaline phosphatase (ALP) and their kinetic parameters 〔maximum reaction rate (V_max), Michaelis constant (K_m), and catalytic efficiency (K_cat)〕 were measured. [Results] ① The soil bulk density (BD), pH value, and enzyme activities of BG, LAP, and ALP per unit of organic carbon all increased with soil depth; however, the soil water content (SWC) and soil organic carbon (SOC) content decreased with soil depth. The highest pH value was in the coniferous forest, and the ammonium nitrogen (NH₄⁺-N) and total phosphorus (TP) contents were in the order of broad-leaved forest＞mixed forest＞coniferous forest. ② The average (comprehensive) soil enzyme activities and K_cat value were in the order of mixed forest＞coniferous forest＞broad-leaved forest. The K_m value were in the order of mixed forest＞coniferous forest＞broad-leaved forest. ③ The specific activities of the four enzymes related to carbon, nitrogen, and phosphorus transformation were significantly negatively correlated with NH₄⁺-N, nitrate nitrogen (NO₃^--N), available phosphorus (AP), and SOC content, whereas the specific activities of BG, NAG, and ALP per unit of organic carbon were significantly positively correlated with pH value. Redundancy analysis showed that SOC content had significant influence on enzymatic reaction parameters in both coniferous forest and broad-leaved forest (p＜0.01). The main factors affecting the specific enzyme activities and kinetic parameters in mixed forest were SOC (p＜0.01) and TP (p＜0.05) content. [Conclusion] The soil enzyme activities per unit of organic carbon and K_cat of mixed forest were higher than those of coniferous forest and broad-leaved forest in loess hill region, indicating that the enzyme catalytic ability in mixed forest was higher than those in coniferous forest and broad-leaved forest. Therefore, mixed forest should be given priority consideration in artificial afforestation to improve soil quality.