The present disclosure provides is a method of manufacturing a flexible pressure sensor by forming the polymer support and the conductive particles from a single uniform solution and performing a curing of the polymer support and a growth of the conductive particles in a continuous process. The method of manufacturing a flexible pressure sensor includes: preparing a solution by adding a polymer support material, a conductive particle, and a photoinitiator to a solvent; applying the solution on a flexible substrate; and irradiating ultraviolet rays onto the solution applied on the flexible substrate to cure the solution and form a solid film.