An increased interest in hybrid drive systems allowing reduction of fuel consumption and emissions of harmful substances into the atmosphere, as well as their partial use as zero–emission vehicles promotes the development of these types of drive systems. The market analysis indicates an increased sale of hybrid drives in vehicles, and this means that actions taken towards of reduction of fuel consumption are still valid. The aim of this article is to indicate the indexes of performance of combustion engines in hybrid vehicles during a part of the type-approval driving test. The article analyses Toyota hybrid vehicles with particular attention paid to the parameters of the hybrid drive system and the influence of the charge level of battery on the share of the combustion engine operation in the total time of the vehicle operation. The analysis was carried out for vehicles equipped with the Toyota Hybrid Synergy Drive system working with different types of high voltage battery.