As a widely adopted ecological agriculture model, the "pig-biogas-fruit (PBF)" system has become a key pathway for the spread of antibiotic resistance genes (ARGs) from poultry manure into agroecosystems via biogas slurry. However, the patterns of ARGs distribution and transmission in biogas slurry of the PBF system remain poorly understood. Nine common ARGs and the Class 1 integron gene (intI1) were detected and quantified in biogas slurry samples from seven PBF farms in Huazhou City, Guangdong, China, using quantitative PCR. Gene abundances were further analyzed across different particle sizes. The results indicated that biogas slurry served as a reservoir for tetC, tetM, tetO, tetW, and sul1. The abundances of these ARGs were significantly higher than those in natural environmental samples, and their levels were comparable to or even exceeded those detected in wastewater and sludge. These findings highlighted the high risk of ARG contamination and its potential spread through the application of biogas slurry. Small particles (<250 mu m) carried significantly more ARGs than larger particles, with network analysis identifying anaerobic genera (e.g., Methanothrix) as dominant ARG potential hosts. Sub-250 mu m particles, acting as primary ARG carriers, necessitate stricter filtration control in anaerobic wetlands like rice paddies. Based on host adaptation patterns, preferential application of biogas slurry in dryland farming (e.g., orchards) is recommended to mitigate ARG dissemination risks, though field validation of host survival rates remains required. This study provides a theoretical basis for improved PBF model management.