A discussion is given on a method of forecasting time (t_γ) to failure in the early period of the Tertiary creep.In cases of landslide and slope failure, the record of the relationship between surface displacement (l) and time (t) is seen under normal conditions. On this displacement-time curve, relationship between Δt and t_γ is shown as follows: t_γ=x (Δt) ⁿ. Here, Δt is the elapsed time to move initial unit length (Δl) of displacement (l) from the start of the Tertiary creep, tγ is the time to failure and a, n are constants, Seven actual types of failure data are used for this analysis and Δl is given as follows: Δl=10, 20, 50cm. As using equation above or t_γ-Δt diagram, we cam approximately predict the failure time in the early period of the Tertiary creep.