Recently, bladed disks with continuous ring type structure have been used in many kinds of turbomachinery due to its high reliability. The vibration characteristics of the bladed disk with continuous ring type structure have been studied extensively, and the effect of the friction damping on the forced vibration is almost clarified. On the other hand, few studies have been done on the effect of the friction damping on the blade flutter. In this paper, the stability analysis of the bladed disk with continuous ring type structure is carried out using the equivalent spring-mass model, and the effect of the friction damping on the blade flutter is clarified. From the results of the analysis, it is concluded that the stable steady vibration or the flutter always occurs when the aerodynamic damping of the blade becomes negative. Whether the blade vibration is stable or unstable depends on the magnitude of the aerodynamic damping and the initial condition. In other words, when the friction damping cannot suppress the self-excited vibration due to the large aerodynamic damping and the large initial amplitude, the amplitude of the blade vibration becomes larger and the flutter occurs.