An image sensor package mainly comprises a main body and an image sensor chip directly attached to a chip-supporting member integrally formed with the main body through an adhesive layer. The image sensor chip is electrically connected to a lead frame integrally formed with the main body. The main body has a wall erected around the image sensor chip with a height taller than the height of the image sensor chip. A optically transparent cover sealed over the top of the wall of the main body thereby allowing the image sensor chip to be exposed to the object to be sensed on an optical principle.