Toppling failure is one of the main instability modes of the vertical slabbed rock slope. However, the current calculation methods of the slope toppling critical height is based on the assumptions that the rock is a linear elastic body, a damage body or a creep body, respectively. However, the rock mass in engineering practices often has the damage and creep properties, and therefore the existing studies cannot meet the practical engineering needs. In this paper, considering the soft rock having both damage and creep properties, the corresponding calculation methods of the slope toppling critical height are obtained based on the classical Euler compression rod model when the rock is assumed as the Maxwell creep body, the Weibull statistical damage body and the combined body with damage and creep properties, respectively. In addition, the effect of the relevant parameters on the calculation results is discussed. The calculation results show that the effect of the mesoscopic damage should be considered in toppling calculation of the vertical slabbed rock slope. When the rock creep property is taken into account, the slope toppling critical height decreases generally following an exponential law with the elapsed time.