In this article, an efficient transient analysis method for high-speed interconnection and packaging problems is proposed. The method is committed to a full-wave generalized partial element equivalent circuit (G-PEEC) model with guaranteed stability and causality. With the proposed method, the full-wave G-PEEC model is represented by a few static compact subcircuits that are derived by applying the micromodeling circuit method to the G-PEEC model at a few discrete frequency points. Its transient response can be obtained by a linear combination of responses of the compact subcircuits, which can be simulated by the transient analysis method of SPICE. By adopting the compact subcircuits, which is an order reduced G-PEEC model, the transient simulation can be speeded up by two orders of magnitude when compared with the case if the subcircuits are generated directly from the G-PEEC model. Since the compact subcircuits are static, physically meaningful, and passive, the proposed transient analysis is with guaranteed stability and causality. Moreover, a frequency compensation strategy is proposed for preparing input signals of subcircuits to avoid the Gibbs phenomenon. Finally, three numerical examples, including eye-diagrams for a practical multilayer interconnection problem, are given, demonstrating the effectiveness, accuracy, scalability, and simplicity of the proposed method.