Flow and heat transfer characteristics of alkali metal liquid in a pipe with inscribed regular polygon porous media are numerically investigated under local thermodynamic equilibrium condition. The effects of filling ways including inscribed regular polygon filling way and segmented inscribed square filling way under different Darcy number (10-6≤Da≤10) are analyzed. The results show that, the velocity near the wall is violently changed by inserting partially filled porous media due to the high resistance of porous media. For inscribed regular polygon filling way, the PEC value of inscribed square is the maximum, which makes it optimal for heat transfer enhancement. For segmented inscribed square filling way, the average Nusselt number increases as the filled ratio increases while decreases as the unit length increases. Owning to the dominant role of the entrance effect, the smaller the unit length is, the larger the PEC is. The PEC of 5:5 segmented filling way is found superior to other filling ways, possibly because the heat transfer enhancement and flow resistance control reach an excellent balance for that case.