Increasing heat transfer in heat exchangers has been consideredin many previous researches. Also the outgrowths of the sinusoidal tube heat exchanger do not have an important role in heat transferring. Using the porous media with a larger contact area with fluid and much larger heat conduction coefficient will increase the heat transfer, and the flow will be better ordered. In this paper, the problem of fully developed laminar flow in a sinusoidal heat exchanger filled with a homogenous porous media in the outgrowths of a sinusoidal tube heat exchanger is considered. Effects of surface waviness are shown by arameter which is the ratio of wavelength to amplitude. As decreases, the waviness of the surface increases. The problem is solved for =11, 19 and 25. The numerical analysis are conducted in Fluent to obtain the optimized thickness of porous media leading to the best performance of the heat exchanger.Performance of the heat exchanger is defined by PEC number which relates heat transfer and friction factor. Critical amount of PEC is one. The effects of Darcy number and porosity are considered. It is observed that mere the Darcy number will change the optimized porous media thickne but, the thickness is not changed with the change in porosity. The performance of the heat exchanger will be maximized when the outgrowths are fully filled with porous media with Darcy numbers between 10 -4 -10 -2 . In this condition, pressure drop is logically increased 8%. For Darcy numbers between 10 -6 -10 -4 , the maximized performance will happen in a lower thickness of porous media. It is shown that this treatment is repeated for all three . For all different umbers between 11-25, the optimized thickness of porous media is less than 100% for Darcy numbers between 10 -6 -10 -4 ; however, after Da=10 -4 , the optimized thickness is 100%, which means fully filling the outgrowths. In all cases, it is observed that increasing the Darcy number will lead to an increase in Nusselt number and heat transfer coefficient. In larger Darcy numbers Nusselt number and heat transfer coefficient are increased 2 times. For Darcy numbers between 10 -6 -10 -4 , there is a mild increase, while for Darcy numbers between 10 -4 -10 -2 the rate of increase is acute. It is shown that increasing the Darcy number will decrease the pressure drop and friction factor. This decrease is an acute trend for Darcy numbers between 10 -4 -10 -2 . In addition, decreasing the porosity will increase the heat transfer rate, and the friction factor will be remained the same; hence increasing the heat exchanger performance. The change in porosity will not affect the desired porous media thickness to improve heat exchangers’ performance. In all cases, it is shown that by using porous media the performance of heat exchanger is improved and the PEC number is more than the critical number. Key Words: Porous Media, Sinusoidal Heat Exchanger, Forced Convec