International Humanitarian Law (IHL) protects the persons who are not or no longer participating in direct hostilities and restricts the adverse utilization of the means and methods of warfare. However, the rapid developments in science and technology & polarized power relations are questioning the ability of the International Humanitarian Law to adapt itself to regulate human conduct, in the circumstances of modern warfare. This study focuses on identifying the new forms of armed conflicts in the 21st century and the contemporary challenges on IHL under the following classifications: (a) Shape of the contemporary battlefield made by the involvement of the parties, (b) Modern platforms of warfare and the new challenges on IHL, & (c) Modern technologies using on the battlefield.