Objective To characterise knowledge, attitudes, and practices (KAP) regarding antibiotic use among Fulani women milk vendors in Sabon Gari and Zaria, Nigeria, within a One Health frameworkMethods A cross-sectional survey of 77 itinerant Fulani women milk vendors employed a structured questionnaire adapted from validated KAP instruments for livestock producers. Items assessed vendor characteristics, antibiotic knowledge, attitudes towards antimicrobial use (AMU), practices, and self-reported use of 21 antibiotics. Data were analysed descriptively in SPSS (version 25). Knowledge and practice items were dichotomised (appropriate = 1, inappropriate/“don’t know”/missing = 0), converted to percentage scores, and categorised as good (≥ 80%), moderate (50–79%), or poor (< 50%). Attitudes were summarised as 7-point Likert means, with scores ≥ 4.0 interpreted as permissive.Findings: Vendors were exclusively itinerant traders, predominantly marketing fermented products (nono, kindirmo). Knowledge deficits were profound: 55.8% had heard of antibiotics, 31.2% recognised their action against bacteria, and none specified side-effects. Overall, 0% achieved good knowledge, 2.6% moderate, and 97.4% poor scores. The mean attitude score was 4.41, indicating uniformly permissive orientations. Practices were frequently unsafe: 59.7% routinely added antibiotics to feed or water, 45.5% retained leftovers, and 22.1% shared them, yielding 2.6% good, 26.0% moderate, and 71.4% poor practice scores.Conclusion Fulani women vendors in Zaria’s informal dairy markets exhibit profound knowledge deficits, permissive norms, and hazardous AMU behaviours, substantially shaping consumer exposure to antibiotic residues and resistant organisms. These findings underscore their importance as priority targets for gender-responsive One Health stewardship interventions.