We present the electronic structure, energetic stability, mechanical, and electronic properties of Mg7XH16(X = Ti, Zn, Pd, Cd) ternary hydride systems using a first principles approach in the framework of density functional theory. The possible usage of these systems in hydrogen storage applications is discussed. The systems under investigation have lower formation enthalpy than conventional MgH2 material indicating lower thermodynamic stability and improved hydrogen releasing capacity. All the systems are mechanically stable and compressible materials with relatively low elastic moduli values. In the electronic aspect, Mg7XH16 (X = Ti, Zn, Cd) systems are metal, but Mg7PdH16 is a zero-gap semiconductor with bands nearly touching at Fermi level (E-F) and zero density of state at E-F. This material can also have possible applications in optoelectronics.