The synchrotron+synchrotron-self-Compton (SSC) model can be used to fit the multi-wavelength quasi-simultaneous data of BL Lacs to obtain the relevant jet physical parameters, which is able to explain the physical properties of BL Lac jets. A great deal of free parameters bring too much uncertainty to the calculation results in SSC model. Due to the spaces of these model parameters are too large, the efficiency of energy spectrum fitting is reduced. Nevertheless, in this paper, we obtain the physical quantities from the multi-band observation data. And we determine the 8 parameters in the single-zone homogeneous SSC model with the broken double-powerlaw electronic injection. What's more, we use the SSC model to calculate two typical BL Lacs multi-wavelength spectral energies to test our determined results. The results indicate that within the determination of 8 model parameters space, we calculate the theoretical photon spectrum with the model parameters, which is in favorable agreement with the quasi-simultaneously observed data of the two BL Lacs.