Stitched composite sandwich panel (SSP) is a typical structure used in aerospace structures. Research work on the dynamic characteristics of SSP is one of the most concerned problems in the design stage of aerospace structures. Taking a typical SSP as research object, the dynamical equation of the SSP is derived and the dynamic characteristics are investigated. Then, the effects of stitching density and stitching angle on the modal characteristics, frequency response characteristics and random response of the SSP are further discussed. Results show that the integrity of SSP can significantly be improved by stitches. The existence of stitches also increase the natural frequencies of the SSP. The stitches restrain the local modal of the SSP, reduce the modal density and decrease the acceleration and response energy on the SSP under acoustic excitation. However, the stitches have little influence on the stress response on the structure. The stitches mainly reduce the dynamic response of the upper panel and have little influence on the dynamic response of the main load-bearing plate. With the increasing of the stitching density, the influence of the stitches on the dynamic characteristics tends to converge. The stitched angle has little influence on the dynamic characteristics of the SSP.