The invention discloses an electromagnetic shielding case based on a micro metal grid and a manufacturing method of the electromagnetic shielding case. The method comprises the following steps that micro metal grid grooves are formed in a flexible substrate according to a micro-nano impressing method; the micro metal grid grooves are filled with nanometer conductive paste in a blade coating mode, and a micro metal grid conductive thin layer is formed after sintering; the micro metal grid is formed in the micro metal grid grooves after electroforming deposition; the deposited micro metal grid is stripped out of the micro metal grid grooves of the flexible substrate, so that the hollowed-out micro metal grid is formed; the hollowed-out micro metal grid is combined with a metal sheet with the same size as the hollowed-out micro metal grid, so that the combined micro metal grid is formed; the combined micro metal grid is fixed to a concave die, and the combined micro metal grid is rolled to have the same shape as the concave die; the combined micro metal grid is separated, so that the electromagnetic shielding case having the same shape as the concave die is obtained. The electromagnetic shielding case is high in manufacturing efficiency, low in cost and capable of being manufactured on a large scale.