A new GFRP sandwich floor panel has been developed in the last few years to replace the traditional timber panel. This panel has acceptable structural mechanical properties to be used in civil engineering applications. The present work focuses on the free vibration behaviour of the one-way, two-way, and continuous GFRP sandwich floor panels. Few different variables were considered in this study; span of the panel, single spanning, continuous spanning, panel restrain types at supports, and skin fibre orientations. The restraints types considered are free, screws, and glue. A 3D numerical finite element model was developed to find the mode shape of different panels. It was found that the natural frequency of this panel is non-linear with respect to span variations. The orientation 0°/90° gives higher frequency than ±45° in the case of one-way spanning panel, and the orientation ±45° gives higher frequency than 0°/90° in the case of two-way spanning panel.