The entanglement properties of three-color and tripartite entangled state produced from two cascaded type I second-harmonic generation cavities are analysed. It is shown that the reflected pump beam of the first cavity, the reflected pump beam and the output second-harmonic beam of the second cavity are entangled, and the dependence of the entanglement degree on various experimental parameters is also analyzed. The scheme provides a reference for generation of multicolor entangled state and its application in quantum measurement and quantum communication.