A simplified process was developed for fabricating natural bio-based fiber-reinforced polymer composites for applications such as automotive interior trim substrates. Biofiber (Kraft pulp fiber) and four types of thermoplastic polymers (PP, two PP/PE polymer blends, and PLA) were first wet-formed into fiber/polymer mats and the mats were made into composites using a match-mold thermoforming process. The effects of void content on the composite tensile and flexural properties were investigated. Impact resistance and heat deflection temperature were tested and acoustic absorption coefficients of the composites were evaluated as well. Two types of prototype panels (2-D and 3-D) containing biofiber/polymer composite substrates with a bonded synthetic leather decorative surface were successfully made using this process. Biofiber/PP composites had comparable performance to the commercially available non-wood natural fiber/PP composite counterparts for the properties investigated in this study at the same density level (0.8 g/cm(3)).