With the constant development of automobile industry in China and the improvement of people's living standard. The requisition for automobile has already expanded to the a great deal of aspects, such as motive force , security , environmental protection, comfortable and appearance ,etc.. It is not merely the private car in all these aspects, the city bus as the most important transportation vehicle is no exception. At present, Beijing transportation bus manufacturing cooperate with Yutong passenger bus company made a investment on the research of new style bus with 12 meters long and the diesel engine according with the Europe ¢ó discharge standard. It is reported that the chassis reform work had already finished and estimated the development work will finish at the beginning of August, the reformed passenger bus with Europe ¢ó diesel engine will appear on the market at the end of 2004.