This paper is a report on study of the characteristics of the ro11 resonance of an asymmetrical re-entry vehicle. The equations of motion are described in a coordinate system which does not spin with the vehic1e. The effects of the spinning of the asymmetrical vehicle on the persistent ro11 resonance has been studied with the linearzation method. Also a formula of spinning speed is derived to avoid the persistent ro11 resonace. It is show that the region in which the persistent ro11 resonance may occur will vary with the spinning speed when it is more slow.