Abstract: A magnetic recording medium is provided comprising a flexible substrate and a ferromagnetic metal thin film layer on the substrate primarily comprising cobalt. When coercive force is measured by changing the measuring direction in a plane defined by a longitudinal direction of the substrate and a direction normal to the major surface of the substrate, the following relationship is met:(Hc.sub.max -Hc.sub.min)/Hc(O).ltoreq.0.9where Hc.sub.max is the maximum of the coercive force, Hc.sub.min is the minimum of the coercive force, and Hc(O) is a coercive force in the longitudinal direction of the substrate. The medium has in average at least 10.sup.5 /a.sup.2 protrusions per square millimeter of the surface, the protrusions having a height of 30 to 300 .ANG., where a is the distance as expressed in .mu.m of a gap in a magnetic head across which the medium is passed for recording and reproducing operation. The filling ratio of the ferromagnetic metal thin film layer is at least 0.7.

Abstract: In a magnetic recording medium comprising a length of a non-magnetic plastic substrate and a magnetic thin layer of Co or Co-Ni or Co-Ni-Cr formed thereon, when the coercive force of the medium is measured by changing the measuring direction in a plane defined by a longitudinal direction of the substrate and a direction normal to the major surface of the substrate, the following relationship is met:(Hc.sub.max -Hc.sub.min)/Hc(0).ltoreq.0.9where Hc.sub.max is the maximum coercive force, Hc.sub.min is the minimum coercive force, and Hc(0) is a coercive force in the longitudinal direction of the substrate.