Magnesium silicate hydrate (M-S-H) binder systems containing reactive magnesium oxide and amorphous silica have been increasingly studied since its cementitious properties were first reported in 2006. This paper presents an experimental study of mechanical and durability properties of a concrete using an M-S-H binder system containing 60% MgO and 40% SiO2. The compressive strength of M-S-H samples at 28 days was approximately 40 MPa. The MSH concrete developed its strength more slowly than the PC mix over the 28 days curing period. Other mechanical properties (split tensile strength and modulus of elasticity) of M-S-H concrete were also lower than the comparable PC samples. Concrete samples using M-S-H binders showed moderate to good durability indexes (porosity, oxygen permeability, resistivity) for durable concretes. The PC concrete samples were generally less porous/permeable and accordingly performed better than M-S-H concrete in terms of durability.