Understanding the evidence-based elements that impact the adoption of organic farming is advantageous for the proper management of such adoption. Our research examines the influence of socio-psychological factors in promoting organic agriculture in Vietnam, including peer influence, social norms and personal norms. Cluster analysis is applied to account for individuals' heterogeneity in environmental beliefs regarding adopting organic farming. We find that peer influence, such as the frequency of communication and the existence of organic farming neighbors, are critical components of organic agriculture. Moreover, social and personal norms could also play a key role in incentivizing environmentally concerned farmers to convert to organic farming. Therefore, policymakers should encourage neighborhood collaboration, establish a channel for farmers to promote interaction between farmers and promote farmers' recognition of the importance of organic agriculture to effectively drive them toward the sustainable adoption of organic farming.