Reservoir is an underground formation with various pores that is able to store oil, water and/or gas, while reservoir acoustics is related to studies and applications of acoustic wave interactions with multiphase porous media. The reservoir acoustics stems from seismic petroleum exploration (including single well imaging, vertical seismic profile, and cross-well tomography), acoustic logging, rock acoustic measurements, sedimentology, digital acoustic signal processing and imaging, and so on, through which it has developed into a comprehensive acoustics branch for the petroleum exploration and exploitation. In this presentation, I will give a comprehensive review for reservoir acoustics and discuss the technical problems in this recently developed acoustics branch with its major applications. This will include the concepts of reservoir acoustics, the research areas of reservoir acoustics, important applications, and future developments. I will focus on the progress of acoustic wave propagation in multiphase porous mediums, time reversal acoustic imaging for seismic data, and hydrostatic pressured fracture detection in enhanced oil recovery using micro-seismics, three-dimensional borehole acoustic well logging. Especially, I will discuss the borehole acoustic mode characteristics for borehole acoustic wavefield representation in complex borehole configurations. Also, I will discuss the applications of borehole acoustic well logging in formation anisotropic identifications, stress evaluations, and so on.