With the help of Fluent 6.2 and supporting softwares，computer 3D numerical simulation of fluid flow and heat transfer enhancement of plastic elliptical oblique teeth flat strip tubes with eddy port were performed，and the flow rate，turbulence intensity and improvement of convective heat transfer coefficient distribution in smooth tubes and plastic elliptic oblique teeth flat strip tubes were analyzed and compared.The results showed that the fluid flow in flat strip tubes was complicated three-dimensional flow，mainly swirling flow.With interference flow by flat strip，flow rate and turbulence intensity increased greatly.Fouling deposition around inner wall was effectively inhibited and heat transfer was enhanced.Compared with smooth tubes，average heat transfer coefficient inside flat strip tubes increased by 45%.The pressure drop caused by oblique teeth flat strip was in the permissible range of engineering application.It was suitable for the heat exchanger at a flow rate lower than 0.8 m8226;s-1.