OBJECTIVE To analyze the serotypes, clinical symptoms and antimicrobial resistance characteristics of Salmonella infections in children aged 0 to 14 years with diarrhea in Guangzhou.

METHOD The basic information, case data, serotypes and antimicrobial susceptibility results of children with Salmonella-positive stool cultures from a maternal and child health hospital in Guangzhou （2018–2025） were collected for retrospective analysis.

RESULTS The overall detection rate of Salmonella from 2018 to 2025 was 22.89% （1 844/8 057）, with a generally increasing trend in annual detection rates （P＜0.001）. The detection rates in the ＜1-year and 1- to 3-year age groups were significantly higher than those in the >3- to 6-year and >6- to 14-year age groups （P＜0.05）. A total of 25 serotypes were detected, with Salmonella typhimurium having the highest proportion. The serogroup composition differed significantly across age groups （P＜0.001）. Diarrhea and fever were the main manifestations in the children. Resistance rates of Salmonella to the tested antimicrobial agents varied significantly （P＜0.001）. Statistically significant differences in resistance rates to ampicillin, ceftazidime, ceftriaxone, ciprofloxacin and trimethoprim-sulfamethoxazole were observed among different serogroups （P＜0.05）. The antimicribial resistance rates to ceftazidime, ceftriaxone, and sulfamethoxazole/trimethoprim showed an increasing trend （P＜0.05）.

CONCLUSIONS Salmonella infections among children in Guangzhou mainly occur in those under 3 years old, with a diverse serotype distribution dominated by S. typhimurium. Salmonella exhibits a high resistance rate to ampicillin, and the resistance rates to ceftazidime, ceftriaxone and sulfamethoxazole/trimethoprim show an increasing trend. Antimicrobial resistance monitoring should be strengthened to guide rational clinical drug use.