The concept of green and sustainable development is driving the convergence of transportation systems and energy technologies. New energy harvesting technology is an important way of the development in the green intelligent transportation system. Comparing with the power supply via batteries or cables, it has the advantages of convenient, sustainable, green and low carbon to harvest mechanical energy from the traffic environment and convert it into electrical energy to power the widely distributed small electromechanical systems. There are many studies on mechanical energy harvesting in traffic environment, few of them have comprehensively discussed these studies and their applications in the intelligent transportation. This paper first outlines the principles, methods, and energy management strategies of the mechanical energy harvesting in the traffic environment. The advantages, disadvantages, and applicability of various energy harvesting technologies are comprehensively and systematically analyzed from vehicle and road dimensions. The applications of energy harvesting technology was discussed includes: self-powered traffic control, self-powered vehicle-road collaboration and self-powered health monitoring of traffic infrastructure. Finally, the challenges and prospects of mechanical energy harvesting technology and applications in the traffic environment are discussed. Mechanical energy harvesting in traffic environment has broad application prospects in intelligent transportation, while improving the output power and reliability of the energy harvesting system is the key to its wide application in intelligent transportation systems.