Abstract: Heat exchangers made of special plastics can solve the problem of low temperature corrosion in flue gas heat recovery, so that the lower limit of temperature restriction can be eliminated. In this paper, polytetrafluoroethylene（PTFE） tube bundle heat exchanger and fin-tube heat exchanger made of thermally conductive plastic were evaluated under the same work condition of a 1 000 MW power plant. Parameters including heat transfer coefficient, heat transfer area, heat exchanger volume, pressure drops were compared between the two types of heat exchangers. Although the PTFE tube bundle heat exchanger has higher heat transfer coefficient and consumes relatively less raw material for manufacturing, the fin-tube heat exchanger has smaller volume and much less number of tubes. Based on the comparison, further studies on fouling thermal resistance and material thermal conductivity were carried out for fin-tube heat exchanger. The results show fouling thermal resistance can lead to 20%~30% of performance variation. And the material thermal conductivity need to reach a threshold value of 15~20 W/（m?K） to achieve satisfactory heat transfer performance.