The main reason of mortality at many roadways of the country is the accidents of heavy vehicles. These accidents cause creating high costs. Lorestan province is the passageway of many heavy vehicles due to its geographical location and being located on the border of the other industrial provinces such as Khoozestan , Markazi, and Esfahan and traffic of such vehicles is very high in the main roads of this province. According to the analysis conducted on the reported accident between the years of 92-93 , the amount of the blamed heavy vehicles increased by 10.69 percent had the highest growth and the fatal and injury accidents of these kinds of vehicles have increased respectively by 6.24 and 14.76 percent. There fore, considering some special measures for controlling the heavy vehicles seems necessary. This research has been provided based on the information and Com 114 records which were recorded by the police of Lorestan province and the analyzes have been performed by using SPSS software. The results of analyzes of heavy vehicle accidents have shown that the axes of the province and a major cause of accidents of this type of vehicles in summary are: 1. Failure to observe the right of way, paying attention to the front, the inability to control vehicle and assault and deviation to the left as the most important factors leading to the accident. 2. collision with a vehicle as most types of accidents 3. overturning, rear-end collision accident occurred and most of the accident 4. drivers aged 25 to 35 years as a high risk group for heavy vehicles Tsadafat 5. Category education diploma and diploma below the literacy level of most of the drivers at fault in the accident 6. The second half of the day as the time when most accidents.