Abstract By applying the PZB gap theorem and its extension of knowledge gap model, this study explores the gaps between the knowledge capabilities needed for social media marketing and what agricultural organizations such as cooperatives or family farms have done from the strategic perception aspect, planning aspect to implementation aspect. This study employs a case study approach combined with a structured questionnaire distributed to top agricultural organizations in Taiwan, focusing on social media marketing within the knowledge management framework. The results of empirical analysis exhibit two gaps significantly impact the corporate performance, namely: the gap between the obtained knowledge capabilities after implementing the social media marketing plan and the actually required ones for the enhancement of corporate competitiveness in social media marketing; the gap between the knowledge capabilities for enhancing corporate competitiveness in social media marketing perceived by senior managers and perceived by employees. Based on the findings, this study suggest the agricultural organizations could try to improve by reducing these two gaps of implementation aspect to improve their performance. Finally, the in-depth interviews with two agricultural organizations could establish a practical understanding of the relationship between these empirical findings and business practices.