A cross-sectional study of 535 nursing students enrolling at Thai Nguyen University of Medicine and Pharmacy during 2021 - 2022 was conducted to investigate attitudes and knowledge of breastfeeding. Results showed that the prevalence of participants with correct knowledge about breastfeeding was 41.94%. The mean score (SD) of breastfeeding attitude measured by the Iowa Infant Feeding Attitude Scale was 58.95 (5.91), which fell in the range of neutral attitude about breastfeeding (55 - 61). The prevalence of students with positive breastfeeding attitudes accounted for 31.4% only. The mean score was statistically significantly higher in students with positive breastfeeding attitudes than those with neutral and/or negative attitudes towards breastfeeding (p < 0.05). Mean scores of breastfeeding knowledge and attitudes varied according to some characteristics including the year of study, cumulative academic average marks, and taking courses in infant breastfeeding (p < 0.05). It is important to promote breastfeeding education in academic programs to equip future nursing students with knowledge and attitude about infant breastfeeding to support mothers who breastfeed.