In this paper, we study the properties of the general three-dimensional equilibrium solutions for steady-state equations of inviscid fluids. Incompressible, homogeneous, inhomogeneous and compressible flows motion in a gravitational potential are considered. General three-dimensional formulas for the gas pressure and the gravitational potential are obtained. For incompressible flows, the vector and scalar potentials of the velocity field are used to derive general formulas for general three-dimensional solutions. To verify our results, some examples are presented. For compressible flows, a class of three-dimensional solutions is constructed.