Antibiotic resistance is one of the greatest public health threats. Since drinking water is paramount for health, concerns about the potential public health risks related to the occurrence and accumulation of antibiotic resistance genes (ARGs) in biofilters for drinking water treatment plants (DWTPs) have been raised. Aiming at profiling the ARGs in drinking water biofilters and evaluating their potential human health risks, a global survey was conducted. Metagenome data of 98 biofilters for DWTPs were collected from the Sequence Read Archive of the National Centre for Biotechnology Information. The abundance of ARGs and their human risk ranks were estimated by referring to a combined database containing 12,253 unique ARG sequences. In total, ARGs conferring resistance to 16 classes of commonly used antibiotics were identified in the investigated biofilters. There was no significant difference in ARG abundance or types between biofilters from different geographic locations (or countries) or using different filter materials. However, significant differences in ARG profiles were observed between biofilters used to treat different types of source waters i.e. surface water or groundwater. The total abundance of ARGs in biofilters treating surface water was approximately five times higher than in biofilters treating groundwater. Risk rank analysis indicated that the majority of the ARGs identified in all biofilters had a low human health risk. For biofilters treating both types of source water, less than 0.5% of identified ARGs were associated with human pathogens. Further analyses indicated that the abundance of ARGs in biofilters used to treat surface water and groundwater was significantly related to the biosynthesis of two different types of antibiotics - prodigiosin and monobactam, respectively. These results indicated that the ARGs in biofilters for DWTPs were more likely generated due to the selection pressure from naturally produced antibiotics rather than from anthropogenic contamination or selection pressure.