BACKGROUNDS: Vaccines are crucial for preventing and controlling diseases in ruminant livestock. However, the effectiveness of vaccination campaigns depends on livestock producers' knowledge, perspectives, and behaviours towards their implementation. Unfortunately, as far as the author knowledge, no studies have been conducted in Bangladesh to assess the knowledge, attitudes, and practices (KAP) status of large ruminant farmers (LRF) regarding vaccine use against infectious diseases. Therefore, the aim of the present study was to address this research gap in Bangladesh for the first time. METHODS: A cross-sectional study was conducted among 244 LRF in selected regions of Rangpur division, Bangladesh. The participants were selected at random, and data was collected via face-to-face interviews with a structured questionnaire. KAP levels were categorized as "good" or "poor" and "positive" or "negative" using a scoring method with a 60 % cut-off. The analysis comprised the utilization of descriptive statistic as well as logistic regression models. RESULTS: The findings demonstrated that most respondents were male (85.2 %), aged 31-40 (32.8 %), with higher education (27.9 %), and vaccination training (28.7 %). While 73.8 % of farmers knew about vaccines, only 39.8 % understood their role in preventing illness from infected animals, and 40.2 % in reducing antibiotic use. Notably, 61.5 % were aware of negative drawbacks, and 59.4 % reported vaccinating their ruminant herds. Most farmers (62.7 %) don't check the expiration dates on vaccine or properly dispose of vials (81.6 %), which poses environmental and public health hazards. Overall, 46.3 %, 55.3 %, and 27.8 % of the farmers had good knowledge, a positive attitude, and good practices, respectively. Multivariable analyses revealed that male farmers aged 41-50 with a higher secondary education, over 15 years of dairy farming experience, and vaccination training were more likely to have good knowledge of vaccine usage. Accordingly, positive attitudes were associated with male farmers with graduate degrees who had vaccination training. Similarly, trained farmers were more likely to have good vaccination practices. CONCLUSIONS: The study reveals farmers' KAP score gaps. It is critical to develop targeted educational and training initiatives to successfully address knowledge and practice gaps regarding vaccine usage and prevent potential large ruminant diseases.