An identification of material properties in each inverse technique based on vibration tests is performed by minimizing the error functional between the experimental and numerical parameters of structural responses. Unfortunately, the dynamic parameters of test specimens are very sensitive to experimental errors and numerical models applied in the identification procedure due to measurement inaccuracies or an approximated nature of the numerical analysis. An influence of numerical model errors associated with the hypotheses used for a material description on identified mechanical properties of laminated composites was demonstrated. For this purpose, two beam-like specimens with different reinforcement schemes have been prepared by using simple manual layout technology. Lamina properties have been identified from vibration tests by using unidirectional and woven composite assumptions.