The invention discloses a drying device for printing plate making of a packaging bag in the field of printing equipment. The drying device comprises a box body and a heating mechanism, wherein articleplacing strips are arranged on two opposite side walls in the box body; the heating mechanism comprises a hot air heating assembly and a microwave heating assembly; the hot air heating assembly is located above the article placing strips; the hot air heating assembly comprises a vent pipe; the vent pipe communicates with an air inlet pipe and air outlet pipes; a heating wire is arranged in the air inlet pipe; one end, far away from the vent pipe, of the air inlet pipe penetrates through the box body and is connected with a fan; the multiple air outlet pipes are inclined obliquely below the inner side of the vent pipe; and the microwave heating assembly is located below the article placing strips. According to the drying device for the printing plate making of the packaging bag, hot air blowing is adopted above a film blank, and heating through the microwave penetration effect is adopted below the film blank; water starts evaporate from the inside of the object through heating, and water starts evaporate from the surface of the object through hot air blowing; in this way, through interior and exterior combination, a pattern layer painted inside a pattern is uniformly dried, and thetechnical problem that an existing drying box is not uniform in drying is solved.