The study aims to test the impact of risk on supply chain cooperation in the agriculture sector in Vietnam. The research paper used the quantitative research method through analysing structural equation modelling (SEM), with a dataset of 518 observations. The survey subject is the experienced and knowledgeable manager in supply chain management in the agricultural sector. The result found that risk has impacted not only directly and negatively on the supply chain cooperation but also indirectly through intermediary factors, namely commitment and the participant's opportunistic behaviour. In addition, the study has also proved that in some cases, the participant's dependency mentality in work and opportunistic behaviour lead to the opposite impact of commitment on trust and level of supply chain cooperation in agriculture. Based on this result, the study also makes recommendations to enhance the effectiveness of the supply chain cooperation in the agricultural sector in Vietnam. The findings contributed to both theory and practice. It pointed out the impact of risk on the supply chain cooperation in the agricultural sector, as well as the mediating role of commitment and opportunistic behaviour in this relationship.