The objective of this paper is to study the filling process of titanium alloy melt in vertical centrifugal casting, as well as the effect of processing parameters on the formation of defects of titanium alloy castings. Experimental results show that the castings obtained in the centrifugal field are better than that obtained in the gravity field. The molten metal sticks to one side of the mould which is opposite to the rotational direction to fill in the vertical centrifugal field. And the cross-sectional area of the molten metal in the runner decreases with increasing of filling length, but has a back-up trend at the inlet of ingate due to the decreases of filling velocity at the ingate. The processing parameters such as rotational direction, rotational radius and rotational velocity play an important role in the formation of defects of titanium alloy castings. Different rotational direction leads to different filling sequence of molten metal, which then affect the following solidification and the formation of the defects. Under the given rotational velocity, the volume of inner defects of castings decreases with increasing of rotational radius and rotational velocity.