This article presents the characteristics of people who inject drugs (PWID) who learned of their HIV-positive status in France between 2016 and 2019, by place of birth, as well as changes in these characteristics since the 2004–2007 period, based on mandatory HIV infection reports. In 2016–2019, IDUs accounted for 0.8% of all reported HIV-positive diagnoses, a percentage that has been declining since 2004–2007 (1.7%). The main trends observed include an upward trend in IDUs over 50 years of age, an increase in the proportion of IDUs without a job, a sharp rise in IDUs born in Eastern Europe and a decrease in those born in France, and an improvement in the early diagnosis indicator among IDUs born in France, which was not observed among those born abroad. Nearly three-quarters of IDUs had never been tested prior to their diagnosis. The growing proportion of IDUs without a job likely reflects a worsening of precarious living conditions. The very high proportion of IDUs who had never been tested before discovering their HIV-positive status indicates that a portion of this population remains disconnected from the healthcare system. These findings call for the promotion of targeted screening and support policies for IDUs and migrants.