This paper presents the transformation of four Maxwell’s equation into relativistic electromagnetism via the partial differential equation of electric and magnetic field with respect to spatial and temporal coordinates. The relativistic form of magnetic field is developed based on Gauss’s law for magnetism and Ampere’s law while the relativistic form of electric field is developed based on Gauss’s law for electricity and Faraday’s law, where and are rest magnetic and electric field. We can easily explain theoretically about the various properties of electromagnetic waves (EM waves) with help of this relativistic formula such as; 1) Why EM waves are not deflected by electric and magnetic field as they have both oscillating electric and magnetic field? ;2) why can’t light travel faster than the speed of light? In this highly interesting topic, the particular purpose is not to enter into the merits of existing theory of relativistic electromagnetism, but rather to present a succinct and carefully reasoned account of new aspect of Maxwell’s equation which properly describe the relativistic nature of magnetic and electric Field.