A chip package structure includes a flexible substrate having a chip mounting region, a plurality of leads disposed on the flexible substrate, an insulating layer and a chip. Each lead includes a body portion and an inner lead portion connected to each other. The body portion is located outside the chip mounting region and has a thickness greater than that of the inner lead portion. The insulating layer is disposed on the inner lead portions. The chip has an active surface on which a plurality of bumps and a seal ring adjacent to the chip edges are disposed. The chip is mounted within the chip mounting region and electrically connects the flexible substrate by connecting the inner lead portions of the leads with the bumps. The insulating layer is corresponding to the seal ring in position when the chip is electrically connected to the flexible substrate.