Scalable shape encoding is an important requirement of highly scalable object-based video coding. In this paper, a new scalable vertex-based shape coding scheme is proposed that uses temporal prediction. During shape coding of a video object, the object shape in the first frame is scalable intra-coded using the method described in M. Hu et al., (2004). For scalable shape coding of subsequent frames, temporal prediction is conducted during the coding of coarser layers. Contour matching in the curvature scale space domain is conducted in order to get higher matching accuracy. Experimental results show that the proposed scalable shape coding scheme can achieve better R-D performance than existing predictive shape coding methods and CAE in MPEG-4.