Abstract: In recent years, antibiotic contamination in landfill leachate and the surrounding environment has attracted more attention. However, there is little information on this subject in Hainan Province. In this paper, three typical landfills in Hainan Province were selected to investigate the contamination characteristics of 17 antibiotics in leachate and surrounding groundwater, including sulfonamides (SAs), quinolones (QNs), lincosamides (LCMs) and tetracyclines (TCs), and to assess their ecological risks. The results showed that: (1) The average detection rate for LCMs in the three landfills was 70.83%, which was higher than that of the other three antibiotics. Among them, the average detection rates of lincomycin (LIN), clindamycin (CLIN) and sulfadiazine (SDZ) were relatively high, reaching 83.33%, 58.33% and 58.33%, respectively. (2) The types and overall levels of antibiotics found in leachate samples and surrounding groundwater samples from the same landfill were similar. The antibiotics detected in the leachate samples with relatively high concentrations of were LIN (1,495.80-10,648.80 ng/L), SDZ (1,473.07-5,910.07 ng/L) and sulfisomidine (SIM, 518.67-1,807.73 ng/L). The antibiotics with high concentrations in the surrounding groundwater samples were SIM (ND-58.10 ng/L), sulfaquinoxaline (SQX, ND-17.77 ng/L), cinoxacin (CNX, ND-27.71 ng/L) and CLIN (ND-18.11 ng/L). (3) QNs had a higher ecological risk level than the other three types of antibiotics; the antibiotics with higher ecological risk levels were sulfapyridine (SPD), SDZ, sulfathiazole (STZ), ofloxacin (OFL), gatifloxacin (GTFX), CNX and LIN. The research shows that some antibiotics in the three landfills are dispersed to the surrounding groundwater through the migration of solid waste and leachate, which brings pollution and ecological risks that need to be paid attention to.