Inverse techniques based on vibration tests and numerical calculations are sensitive to model errors, which bring discrepancies in the results of the estimated parameters. In the present study, model errors related to geometrical simplifications of a laminated plate were considered. The investigation focused on the they have on dynamic characteristics of the plate. Two types of inverse techniques were then used to show the model errors influence on identified material properties. The first was the inverse technique based on the design of experiments and response surface methodology, whereas the second was the iterative inverse technique. In both methods, an error functional between measured and calculated responses was minimized in order to search for an optimal set of material properties. Dynamic characteristics of the plate mostly affected by the model errors were established from a numerical study. They were then eliminated from the objective function reducing the estimation error of the identified material properties.