The present invention discloses a microlens array sheet of a projection screen including a lens sheet having a predetermined area, microlenses arranged on one surface of the lens sheet in the horizontal and vertical directions, a black matrix including apertures corresponding to the microlenses, and being adhered to the other surface of the lens sheet, an optical diffusing layer formed on the lens sheet to cover the black matrix, for widening a viewing angle, and a protecting film for protecting the optical diffusing layer. The microlens array sheet of the projection screen is manufactured by using a process for manufacturing a semiconductor device, a reflow process and a plating process for a mold, thereby improving luminance and definition of the projection screen at a low unit cost of production.