A series of polystyrene/poly(ethyl acrylate-n-butyl acrylate) [PS/P(EA-nBA)] latex interpenetrating polymer networks (LIPNs) were synthesized by the two-stage emulsion polymerization method. The influence of composition, crosslinker content, chain transfer agent, polar group, and feeding sequence on the damping properties of the LIPNs were investigated with a Rheovibron Viscoelastometer. The results show that the PS/P(EA-nBA) LIPNs are a partially miscible system, and that LIPNs favor the broadening of the damping temperature range. The influence of crosslinker content of network I on the damping properties of the LIPNs is not the same as that of network II. The damping properties of the PS/P(EA-nBA) LIPN is superior to that of P(EA-nBA)/PS LIPN. Moreover, the introduction of polar groups into the system can increase the damping properties, and adding chain transfer agent can broaden the damping temperature range.