Two experimentally feasible schemes are proposed for generating multipartite entangled states of cold trapped ions. In the first scheme, a Greenberger-Horne-Zeilinger state can be simply synthesized in a single step, in view of decoherence mechanism, a reduction of the number of operations for the state preparation is crucial. What’s more, only one laser beam is required in our scheme. The second scheme is to prepare canonical (fully symmetric) W states by two steps. However, in the paper [HÄaner H, HÄansel W, Roos C F, et al. Nature, 2005, 438:643-646.] M steps were required for generating the same W states.