In recent years, hybrid natural fiber–reinforced composites prepared by bio-based epoxy resin (BBER) have gained extensive usage due to their exceptional specific strength. Researchers have looked at natural fibre/BBER composites because of the vast array of technical uses for these materials. Experimenting with various composition combinations of hybrid natural fiber composites to improve their mechanical properties requires a significant amount of resources. The purpose of this research was to develop and evaluate a tannic acid (TA) – based bio-based epoxy resin (BBER). The synthesized BBER was analyzed using FTIR spectroscopy. The bio-resin’s thermal characteristics were assessed using TGA, DSC, and OIT studies. Further, this study investigated the mechanical characteristics of hybrid composites prepared by Holoptelea integrifolia (HIBF) bark fibre reinforced with Ziziphus jujuba Seed Particles (ZJSP) which was manufactured using BBER. In the present study, a full factorial design was used to conduct experiments, which included three variables: the percentage of HIBF fibre by weight, the particle size of ZJSP, and the percentage of ZJSP by weight. The experimental results from the mechanical evaluation of the hybrid HIBF/ZJSP using BBER composites are then used to develop a fuzzy model that predicts mechanical parameters such as tensile strength (TS), flexural strength (FS), and impact strength (IS). An accurate prediction of the mechanical characteristics of hybridized composites made by the fuzzy model owing to the membership functions that were built. To further validate the fuzzy model, a set of tests utilising test cases were conducted. The model’s accuracy in predicting the mechanical characteristics of hybrid composites was determined to be 87 % based on the outcomes of the test cases.