NOVELTY - The apparatus comprises a rotary drum rotated by a driving unit for rotating and reeling a polymer spinning solution along an outer periphery of a flexible substrate; an electrospinning unit applying high voltage to the drum for spinning fibers attaching to the substrate, an electrostatic spray unit applying high voltage to the drum for attaching precursor fibers to the substrate, a static electricity spray unit providing electrostatic force to the precursor to from electrospun fibers, an electrostatic spray coating layer formed on surface of substrate.    USE - The apparatus is useful for producing a hybrid coating layer on a flexible substrate of a solar cell, where the apparatus is employed in a filter, an optical fiber, a protecting fabric and a drug delivery system.    ADVANTAGE - The hybrid coating layer is uniformly formed by mixing the precursor and the fiber using the electrospinning unit and the static electricity spray unit on the flexible substrate.    DETAILED DESCRIPTION - The apparatus comprises a rotary drum rotated by a driving unit for rotating and reeling a polymer spinning solution along an outer periphery of a flexible substrate through separate rotation; an electrospinning unit applying high voltage to the rotary drum for spinning fibers attaching to the flexible substrate, an electrostatic spray unit applying high voltage to the rotary drum for attaching precursor fibers to the flexible substrate, a static electricity spray unit providing electrostatic force to the precursor discharged by the electrostatic spray unit to from electrospun fibers wound on the flexible substrate by rotating the rotating drum connected to the ground power, where the electrospinning unit and the electrostatic spray unit are arranged to be spaced apart from each other along the direction of rotation of the rotating drum and an electrostatic spray coating layer is formed on the surface of the flexible substrate by the electrospinning unit and the static electricity spray unit. The fiber is formed by electrospinning of the polymer spinning solution by the electospinning unit so that the discharged fiber has hydrophobicity or hydrophilicity characteristics according to UV irradiation. A control unit controls the operation and rotation speed of the rotary drum. A drum transport unit is used for moving the rotary drum to the rotation axis direction. The drum transport unit is operation-controlled by the control unit. An electrospinning nozzle is located in a separate transport section of the electrospinning unit for spraying the polymer spinning solution. A spray jet nozzle is located in a separate injection nozzle transport unit.