A parametrization method is reported to calculate the electric-dipole transition intensities within the 4f2configuration in LiYF4:Pr3+ by considering the main perturbing component of 4f5d. On the basis of calculating the energy level of the 4f5d configuration, the main 4f5d components that can mix with the4f2 transitional states are determined. We exhibit the calculated densities of the 4f5d states which can mix with the initial and the final states of 3P0 energy level in Pr3+ doped LiYF4. Whereafter a new set of phenomenological intensity parameters, Tkq, is put forward. In addition to the explicit static-coupling mechanism, the approach is extended by the non-explicit dynamic mechanism. Detailed description of the calculated method is brought out. The results of present fitting are compared with that obtained by the traditional parametrization scheme and obvious improvements are exhibited.