This paper focuses on a class of regime-switching functional diffusion processes with infinite delay and develops a central limit theorem (CLT) for additive functionals under uniform mixing conditions. In addition, a law of iterated logarithm (LIL) for the additive functionals is also established by using the square integrable martingale difference sequences. Finally,a Freidlin-Wentzell type large deviations principle (LDP) is established by using an extended contraction principle and an exponential approximation argument under a local one-side Lipschitz condition.