Diversification of smallholder rice-based cropping systems has the potential to increase cropping system intensity and boost food security. Crop diversification is the process of farming multiple varieties of crops from the same or other species in a given region through rotations and/or intercropping. The fundamental feature and most well-understood idea of crop diversification is the addition of more crops to the existing cropping system, also known as horizontal crop diversification (Joshi et al., 2004; Adjimoti and Kwadzo, 2018). Crop diversification is a sustainable and cost-effective strategy with various benefits for agricultural systems and the overall livelihood of the farmers. As a densely populated country, Bangladesh has always struggled to ensure food security. Given the country's food security and employment crisis, crop diversification research in Bangladesh is crucial. The major goal of this study is to provide a better understanding of the crop diversification in Bangladesh. By achieving this goal, first, this study can inform interested parties about the current status of crop diversification in northern Bangladesh. Second, this study might assist the readers in better understanding the aspects that drive diversification practice. Finally, it would help to comprehend the attitude, knowledge, and motivation of farmers as well as difficulties and opportunities involved with crop diversification. The research was carried out in Mithapukur Upazila of Rangpur district which falls under the Eastern Gangetic Plains. Following the multistage random sampling, face-to-face interviews were employed to collect primary data from 122 farmers in the year 2023. We examined the crop diversification status using Simpson Diversification Index, Ogive Index, and Herfindahl Diversification Index. The average Simpson Index, Ogive Index, and Herfindahl Diversification Index were found to be 0.729, 3.925, and 0.270, respectively, indicating that most of the studied farmers are having a high degree of crop diversification. Further, we found a total of 34 types of crops were cultivated in the study area with a cropping intensity of 286% which is higher than the national average of 190%. To analyze the determinants of crop diversification a Tobit regression model was employed which revealed that age, education, household size, farm experience, non-farm income, credit, and mobile access to agricultural information are major determinants of crop diversification. The study further assessed farmers’ attitude and knowledge towards crop diversification using a Likert scale. Most of the farmers also revealed that reducing financial risk is the primary reason for practicing crop diversification. Following that, we looked into several problems that farmers face when diversifying their crops. Pests and diseases had the highest problem index score of 205 that effects of doing multiple crops. Finally, farmers’ suggestions were reported to enhance crop diversification. The outcomes may provide valuable insights for policymakers, planners, and the agricultural sector to foster a more diversified, resilient, and sustainable food system in the Eastern Gangetic Plains.