Aiming to reveal the change law of modeling parameters of the grey model with time-power resulted from a small perturbation of primitive sequence, the spectrum condition number of the matrix is taken as a tool of measuring the morbidity of this model, and the value of conditions of the coefficient matrix with the background value and time-power item of this model in different cases, respectively. The research result shows that this grey model has no unusually severe morbidity. The research conclusion suggests that, in the grey prediction modeling process, while using this grey model with time-power, the solution of this model will not occur significant drift for the original data series of systems existing minor errors.