Abstract: This investigation deals with the effect of using magnetic water on some mechanical properties of concrete like compressive, tensile and flexural strength of concrete and also, the effect of magnetic water on fresh concrete like slump value. The results show that when using magnetic water instead of tap water, it gives higher values of all mechanical properties and more fluidity performance (higher workability) of concrete and that is good property to make concrete need less energy in construction such as less vibration of compaction and workable concrete can enter dense reinforcement without problems and without any formation of voids or air cavities that lead to less strength and durability, therefore, that behavior of magnetic water can make construction in less cost and higher durability comparing with tap water. Results show that compressive strength for 28 days magnetic water had compressive strength of (36.51 MPa) comparing to ordinary concrete using tap water that had (28.94 MPa) compressive strength and the increment here is about 26.2%. And also, increasing the period of magnetism leads to increase the value of compressive strength gradually. The flexural and tensile strength also increased when using magnetic water and workability also improved in this investigation. Microscopic photos of magnetic and tap water in addition to environmental characteristic tests of these two types of water clarified that the suspended particulates in magnetic water begin to split and arrange. This state of magnetic water help it to fill the voids inside dry mixture of concrete better than tap water and work to improve its mechanical properties. This result can give a quick digital test for water magnetism in the field help the users to choose the optimal discharge of water, retention time inside magnetic field and the necessary power of magnets.