Vegetable farmers are facing a number of challenges including price fluctuations, production and marketing problems, low level of income etc. One strategy to overcome these problems is adoption of Good Agricultural Practices (GAP) in vegetable production. However, there is limited information regarding farmers’ awareness of GAP and its applications under the circumstances of farming in the country. Therefore, assessing farmers’ attitude is a timely requirement for directing farmers towards good agricultural practices. Thus, the objectives of the research were to assess the level of awareness of GAP program, relationship between socio-economic factors and awareness of GAP, farmers’ attitudes towards GAP program, factors affecting the willingness to adopt GAP program and the potentials and constraints in implementing GAP program in Galle District. A sample of 100 vegetable farmers in the district was selected through a multi-stage simple random sampling technique. Data were collected from March to July 2018, through a self-administered questionnaire survey and analyzed using descriptive statistics and chi-square test. The results revealed that the majority of vegetable farmers in the district were middle-aged males who had studied up to GCE ordinary level and they received a monthly income of 24000 LKR. Their age, gender, educational level and experience were significantly associated with the level of awareness of GAP program. However, despite their positive attitude towards GAP, most farmers were unwilling to take a risk to adopt GAP due to many issues such as lack of required inputs, capital, required field conditions, information and technical know-how. There are several potentials and also many constraints for implementing GAP in the district. Therefore, providing firstly better theoretical knowledge and then providing the main requirements will motivate more farmers to adopt GAP in their vegetable production procedures. Research studies related to application of GAP by Sri Lankan farmers are still at a lower level. This research thus will be useful for different stakeholders related to adoption of GAP in Sri Lanka.