In order to make full use of engine exhaust heat, the thermoelectric module been used to contribute to thermoelectric power generation in the automotive. At present, the thermoelectric generators (TEGs) have been developing with continuously advances in thermoelectric technology. And almost all of the existing thermoelectric technologies are adding a gas tank to the vehicle exhaust system which increases the exhaust back pressure and occupying excessive space of the vehicle chassis. In this study, a new TEG integrated with a front silencer muffler (FMTEG) is proposed. The muffler is reshaped as the heat exchanger which has a hexagon cross-section. The water tank and clamping mechanism have been redesigned for the new heat exchanger. The FMTEG system’s dimensions are small that can well meet the installation requirements and has a good compatibility with the vehicle exhaust system. The multi-dimensional computational fluid dynamics (CFD) models have been built to simulate the transmission loss (TL) of the noise, thermal field, pressure field of the integrated heat exchanger. The maximum output power has been calculated. The simulation and calculation results show that FMTEG have a better thermal performance and output power performance than the hollow structure. It has a lower back pressure about 250pa. Meanwhile, the average transmission loss of the FMTEG is about 15dB. The FMTEG’s acoustic performance has been proved that it can meet the requirements of the vehicle. Consequently, the use of the FMTEG with better performance could be effectively achieved.