Dynamical systems are inevitably subject to noise perturbations, making the study of the stability of dynamical systems under noise perturbations a fundamental problem. Often used to characterize the complexity of dynamical behaviours, invariant measures, especially the physical ones, are believed to be stochastically stable. This is well-known for hyperbolic systems but remains widely open for more general systems. The main purpose of this talk is to present our recent results on this issue for conservative systems or systems having conservative quantities. A special attention will be paid to the “strong” stochastic stability of invariant measures and its potential applications.