The meshless generalized finite difference method is applied to solve the problem of seismic wave propagation. Schemes in generalized finite differences are obtained for the decoupled system P-SV and SH in homogeneous media and its stability is analyzed. Heterogeneous schemes in generalized finite difference for heterogeneus media, made up of different layers or subdomains are also obtained, considering a linear variation of the parameters at the interfaces. As the method allows using an irregular distribution of nodes, the order of approximation is preserved. Several examples are presented to show the accuracy of the proposed methodology.