In order to study the role of sintering neck in porous titanium with helical pores, the effect of size and position of sintering neck on compressive mechanical properties of porous titanium single cell was studied by using numerical simulation method. The results show that the compressive mechanical properties of the porous titanium unit cell are determined by the helical pore structure and sintering neck. Contribution coefficient of sintering neck is approximately 3.5 times larger than that of helical pore structure. With the increase of the relative diameter of sintering neck, compressive yield stress and elastic modulus of the cell are constantly increased. The sintering point of C1 is the most important sintering position. Under the same condition, increasing the size of sintering neck at C1 is much effective to the increasing of compressive properties.