Based on the integral equations of internal strain fields in elastic bodies containing inclusions, the deformation coordination tensor of inclusions in three-phase composites is derived. Compared with the traditional Mori-Tanaka method (M-T method), the deformation coordination tensor takes into account the distribution characteristics and interactions of inclusions from the perspective of micromechanics, leading to a modified M-T method for predicting the effective elastic properties of composites. Combining with the two-step homogenization model, a method for predicting the effective performance of hybrid fiber composites is derived. Additionally, a prediction model for the tensile strength of hybrid fiber composites is established based on the damage mechanics theory. This method is used to predict the effective elastic properties and tensile strength for coconut husk fiber/glass fiber reinforced phenolic resin composites reported in the literature, and compared the predicted results with experimental data. The results show that the proposed modified M-T method has better predictive ability than the traditional M-T method, with the predicted results and experimental data differing by less than 10.485%. The method is used to quantitatively analyze the effect of the content of coconut husk fiber and glass fiber on the effective elastic properties and tensile strength of hybrid fiber composites. The results show that the effective elastic properties and tensile strength of hybrid fiber composites increase with the increase of glass fiber content.