Wood-based paper fiber composites are of interest due to favorable mechanical properties of the fibers. Wood fibers were separated from sapwood of spruce by a sulfite cooking procedure with 2, 3, 4 and 5 hrs cooking times. Oriented fiber mats were manufactured from these fibers, which were mildly treated as compared with commercial paper fibers. Composites were produced with fiber volume fractions in the range 17.6-19.5%. Scanning electron microscopy, mechanical testing and micromechanics modeling of composites modulus were methods used. Mechanical property data from the literature were compiled and compared with the present results. Young's modulus and strength were 6.4-8.4 GPa and 59-115 MPa respectively. Differences were mainly attributed to differences in fiber orientation distribution, but advantages were noted with longer cooking time fibers separated into individual wood cells. If the low fiber content is taken into account, this material has high stiffness and strength compared to results found in the literature.