The social dimension of red tide phenomenon is one of the fundamental pillars in coming up with holistic plans and programs for a resilient society. Exploring its underlying factors will provide valuable insights to the community for appropriate behaviors and decisions when faced with red tide related challenging situations. This study aimed to develop a tool that will assess the social dimension measures of red tide. It utilized exploratory sequential mixed methods research design. Literature reviews and in-depth interviews were used to gather qualitative data as a basis in the generation of items. An Exploratory Factor Analysis was employed to discover the underlying latent structure of the test. A 45-item scale with three-factor model was developed with the labels: Knowledge, Beliefs and Practices. Statistically, the Knowledge, Beliefs and Practices Scale showed excellent overall internal consistency (?= .93) with strong coefficient alphas for Knowledge (?= .90), Beliefs (?= .82), and Practices (?=.73) factors. A confirmatory factor analysis is carried using the PLS-SEM. The instrument exceeds the minimum requirement of the assessments for the convergent validity, discriminant validity, and reliability. The findings suggest that the proposed developed 45 items Knowledge, Beliefs and Practices Scale (KBPS) is valid and reliable for exploring the social dimension of red tide phenomenon. Thus, the use of the KBP Scale is highly recommended in generating information for social dimension of red tide, which then serve as inputs in strengthening the mitigation efforts for harmful algal blooms.