Four governing equations are derived to describe the fluid transients and induced structural responses of a fluid-filled pipe system. The equations include the coupling terms related through Poisson's coefficient, friction, and fluid-conveying in the pipeline. The method of characteristics (for fluid transients) and finite element method (for structural analysis) are used. A feedback-loop-iteration approach is adopted to solve the coupled problem. A numerical example problem is presented to investigate the fluid-structural interaction responses. The characteristics of a secondary pressure waves riding on the principal transient waves are presented.