Magnetized water is an emerging technology in the construction industry. The benefits of using magnetized water in the production of concrete have been found significant in the present study. This paper describes the experimental study conducted by casting 150 copper slag concrete samples prepared with tap water and magnetized water to investigate the influence of magnetized water on the compressive strength, flexural strength and split tensile strength of concrete which contained copper slag. Water used for mixing the concrete was passed through a magnetic field of 1 Tesla. The decrease in the surface tension of tap water after magnetization was found to be 7.77%. The percentage of replacement of cement with copper slag was 0%, 10%, 15%, 20% and 30%. The results indicate that there was an increase in the compressive strength of concrete by 4-18% when mixed with magnetized water in comparison with the concrete mixed with tap water. Similarly, the split tensile and the flexural strength of concrete mixed with magnetized water was increased 6-17% and 5-10% respectively more than that of control mix. It was also determined that workability of magnetized water concrete containing copper slag was increased up to 50%. The microstructure of copper slag concrete prepared with magnetized water have large amount of C-S-H in comparison with tap water. It was observed that concrete with 85% cement + 15% copper slag shows the maximum strength parameters in comparison with other concrete mixes. © 2017 Elsevier B.V., All rights reserved.