Abstract: Abstract: The integration of agriculture, culture, and tourism (ACT) is an important pathway to address development challenges in border rural areas. It plays a vital role in maintaining border stability and prosperity and in promoting comprehensive rural revitalization. Based on panel data from nine border provinces in China from 2013 to 2023, this study adopts a two-way fixed effects model, a mediation effect model, and a threshold regression model to systematically analyze the multidimensional impacts of ACT integration on comprehensive rural revitalization in these regions. The results show that both ACT integration and rural revitalization in border areas have generally shown an upward trend with some fluctuations. While the level of rural revitalization is relatively balanced, the level of ACT integration varies significantly across regions. ACT integration significantly contributes to rural revitalization, and urban-rural integration serves as an important mediating mechanism in this relationship. The positive impact of ACT integration follows an inverted U-shaped pattern along with the progress of regional economic development and the non-agricultural transformation of the labor structure, characterized by gradual improvement, rapid growth, and eventual slowing down. Further analysis indicates that the promoting effect of ACT integration is more evident in border areas with higher levels of service sector development, stronger government support, and higher rural household income. Moreover, the effects vary across dimensions, with greater impacts observed in cultural revitalization, organizational revitalization, and industrial revitalization. Based on these findings, it is suggested to promote coordinated development in border areas, foster innovation in ACT integration models, accelerate urban-rural connectivity, and establish a coordinated mechanism involving government support, industrial upgrading, and shared benefits. This will help address existing gaps and achieve the integrated advancement of multiple objectives in comprehensive rural revitalization.