The parasitics from packages can obviously degrade the overall performance of the packaged laser diode at high frequencies. Two novel equivalent methods, namely predication method and evaluation method, which can be used to analyze the influence of through-hole (TO) packaging on the high frequency response of laser diode, are deduced from the relation between the scattering parameters of laser diode before and after packaging. In the experiment, TO packaged laser module is taken as an example to investigate the high-frequency influence of the TO packaging. The coherence between the experimental results from the novel method and that from traditional comparison method show the effectivity of the methods. It also can be seen that the TO packaging does not reduce the bandwidth of the packaged laser diode, which means that TO packaging can achieve a frequency bandwidth of 10 GHz, furthermore, the resonance among the circuit elements of TO packaging provides compensation for the frequency response of the devices. The two methods are useful for screening and optimizing the packaging of high-speed optoelectronics devices.