Objective To analyze the local human immunodeficiency virus （HIV） infection characteristics and influencing factors of newly reported HIV infected cases and acquired immunodeficiency syndrome patients （AIDS） in Ningbo City from 2017 to 2020， and to provide scientific basis for local effective AIDS prevention and control measures.

Methods From January 1， 2017 to December 31， 2020， the newly reported HIV/AIDS patients in Ningbo were recruited and face-to-face questionnaire was used to collect relevant information such as demography， behavior， infection route and infection location of research subjects. The data were processed and analyzed by EpiData 3.1 and SPSS 23.0 software.

Results A total of 449 newly reported HIV/AIDS patients were recruited and 399 cases completed the survey. The survey subjects were mainly male （346， 86.7%）， unmarried （188， 47.1%），with local household registration （246， 61.6%）， with junior high school and lower education level （195， 48.9%）， and 25 to 44 years old （206， 51.6%）. The local HIV/AIDS infection rate was 68.4% （273/399）， among which the local HIV/AIDS infection rate of homosexual transmission was 74.9% （146/195）. Multivariate analysis showed that heterosexual transmission of HIV infection （OR=0.349，95%CI：0.201‒0.606）， using dating software to find local sexual partners （OR=2.133，95%CI：0.201‒0.606）， and received no AIDS education services before HIV confirmation （OR=1.914，95%CI：1.196‒3.063） were the influencing factors of local HIV/AIDS infection （P<0.05）.

Conclusion The newly reported HIV/AIDS in Ningbo mainly infects HIV locally， and the coverage of HIV/AIDS education is insufficient before HIV confirmation. A high proportion of local HIV/AIDS infections is found in people who find local sexual partners through dating software and who infected through homosexual transmission before HIV confirmation. It is necessary to strengthen local HIV/AIDS education and Internet intervention among MSM who seek sexual partners through dating software.