[Objective] Ammonia-oxidizing archaea (AOA) is considered the main microbial group catalyzing the nitrification process in acidic soils. However, how AOA adapts to acid stress remains largely uncertain, and we hypothesize that the gene encoding ATPase for microbial energy metabolism may likely play a key role in the adaption of AOA to acidic stress in these soils.[Method] In this study, 736 billion base pairs were obtained by ultra-deep metagenomics sequencing of acidic soils of Masson pine plantations with five different planting years (15 a, 24 a, 45 a, 55 a, 63 a). The phylogenetic congruency between the AOA amoA gene and ATPase subunit A gene was reconstructed to study the molecular mechanism that may enable the acidophilic lifestyle of AOA.[Result] The habitat expansion of AOA to the acidic environment cannot be explained by the phylogenetic evolutionary trajectory of canonic amoA genes encoding ammonia monooxygenase. The dominant AOA taxa from all 5 forest soils were phylogenetically affiliated with Nitrososphaerales and Ca. Nitrosotaleales based on amoA gene phylogeny. Even though Nitrososphaerales is more distantly related to Ca. Nitrosotaleales, it is more closely related to neutral AOA in alkaline soils. Therefore, the phylogenetic law based on the amoA gene cannot explain the successful colonization of Nitrososphaerales in acidic soils. The phylogeny of ATPase subunit A genes indicated a single clade of AOA in all acidic forest soils. These results thus suggest that during the habitat expansion and evolution of AOA, the amoA and ATPase genes could have experienced different selection pressures to cope with acid stress, and the V-ATPase gene may be obtained through horizontal gene transfer to adapt to acid stress. With the increase in forest age, the abundance of Ca. Nitrosotaleales group first decreased and then increased, while the abundance of Nitrososphaerales group first increased and then decreased. Also, it was observed that soil bioavailable potassium is an important environmental factor that significantly affects the structure of the AOA community.[Conclusion] These results indicate that the AOA populations in acid plantation soils under different planting years were clearly differentiated, and the horizontal transfer of V-ATPase gene may be an important mechanism that enables AOA to survive acidic stress for the habitat expansion.