The main objective of this study was to prepare polyurethane foam reinforced with local Turkish natural resources. In this work, olive kernel and nutshell fibers were used for reinforcing the polyurethane foam. In order to characterize reinforced polyurethane samples, mechanical, chemical, thermal, and morphological methods were used. Mechanical properties of polyurethane foam were measured by compression test. With compression test, it was observed that compressive strength of polyurethane foam was increased with 2.5 wt % olive kernel. Functional groups of polyurethane foams were determined by Fourier Transform Infrared Spectroscopy. Thermal behavior of polyurethane foam was analyzed with thermogravimetric analyzer device. Among biocomposites, polyurethane foam filled with nutshell indicated higher thermal degradation than polyurethane foam filled with olive kernel. Scanning electron microscopy observations revealed that foam structure was formed with biofiber addition.