Maternal and child health, which is integral to public health, depends on maintaining a healthy diet during pregnancy and lactation to achieve optimal outcomes. This study aimed to investigate the prevalence and determinants of minimum dietary diversity (MDD) among pregnant and lactating women (PLW) in this particular context. A stratified cluster sampling approach was employed, encompassing intervention areas (Rangpur and Nilphamari in Bangladesh) as strata, with 30 clusters. The study included 631 pregnant and lactating women (PLW) aged 15 to 49 years, focusing on their consumption of a minimally diverse diet. The outcome variable was binary: MDD (1 = if they consumed ≥ 5 food items from a basket of 10 food groups, indicating they met the MDD; 0 = if they consumed < 5 items, indicating they did not meet the MDD), assessed based on ten food groups over a 24-hour period. The data were analyzed using a binary logistic regression model. The study found that 51.19% of PLW met MDD criteria, indicating positive dietary practices. Those aged 21-49 years had significantly lower odds of meeting MDD than those aged 15-20 years. Education played a key role, with completion of primary (p = 0.029) and secondary incomplete education (p = 0.055) associated with higher odds of meeting MDD. Other identified predictors included climate-smart techniques for agriculture, women's empowerment, food security, producing legume, nut and seeds and negative impact on family expenditure due to increase in commodity prices, especially food prices. Employing climate-smart agriculture increased odds by 1.58 times (p = 0.028), empowered women had 2.31 times higher odds (p < 0.001), and food security played a crucial role (p = 0.006). Moreover, producing legumes, nuts, or seeds was significantly associated with higher odds of meeting MDD (OR = 1.55, p = 0.039), while experiencing negative economic impacts lowered the odds (OR = 0.63, p = 0.034). The study provides insights into factors influencing MDD among PLW in northern Bangladesh. Empowering women and promoting climate-smart techniques for agriculture emerged as pivotal determinants, alongside enhancing education levels, increasing food security, and addressing economic barriers. Implementing multifaceted interventions that consider socio-demographic diversity, economic disparities, and dietary preferences is crucial for enhancing dietary diversity and improving health outcomes in this vulnerable population.