The article deals with the problem of continuous speech recognition of Czech language. The main goal of this study is to compare various kinds of bigram language models with respect to the accuracy and speed of speech recognition. The main types of bigram language models are described here as well as multiple parameters that affect the performance of a speech recognition system. A comparison with a zerogram model is also made. Different models and various parameter settings are compared by means of the accuracy rate in extensive experiments done with a large test database of 1,600 Czech sentences recorded by 40 speakers.