Excessive use of agrochemicals in vegetable cultivation has led to several problems, including serious health and environmental issues. Therefore, farming with low-external inputs (LEIs) is inevitable for enhancing safety and security. Thus, the study investigates the need for capacity building on low-external-input techniques, identifies factors that may influence the need for capacity building, and explores the challenges faced by vegetable farmers while using low-external inputs for vegetable cultivation. The study, conducted in Daudkandi and Sherpur Upazila of Cumilla and Bogura districts, involved 400 farmers surveyed face-to-face using a structured questionnaire. The findings revealed that 69% farmers acknowledged a pressing need for capacity development in LEI practices. Factors such as education, family income, training participation, social mobility, extension agent engagement, and food safety awareness were found to significantly influence the need for capacity building. In addition, key challenges faced by farmers during LEI adoption included inadequate technical expertise, suboptimal results, and insufficient method demonstrations. Extension officials are encouraged to prioritize the identified capacity-building needs and emphasize the dissemination of agrochemical-related information to vegetable farmers to prevent input dealers from promoting their use. These measures can empower farmers to adopt safe and sustainable LEI practices, enhancing both vegetable quality and environmental health in Bangladesh.