Systems with slight Coulomb friction at a supporting point have a very small dead zone in which the system stops after free oscillation. The small stiffness makes the dead zone very wide, even under slight Coulomb friction, because it is determined according to the ratio between Coulomb friction and stiffness. Results of a previous study clarify both theoretically and experimentally that in the neighborhood of buckling point, slight Coulomb friction produces a large dead zone around the stable and unstable equilibrium states of the pitchfork bifurcation in the case without Coulomb friction. Therefore, it is important in analyses of behavior of low-stiffness systems such as flexible structures used for spacecraft, to estimate the value of Coulomb friction at a supporting point. In this paper, we describe an experimental identification method for the bending moment attributable to Coulomb friction at the supporting points of a hinged-hinged beam. The moment attributable to dynamic friction is identified from experimental free oscillation by separating the effects of viscous damping and dynamic friction. For static friction, we use the equilibrium region in the bifurcation diagram because of static friction. In the vicinity of the buckling point, the region is very wide. Its boundary is obtained easily through experimentation. We describe a method for identification of the moment because of the static friction from the experimentally obtained boundary.