Abstract: Disclosed is a cap for a packing-bottle capable of packing other auxiliary internal medicine than a liquid medicine. The cap can accommodate a capsule, a tablet, a granular medicine and a powdered medicine, and the cap has a structure easy to use and treat. The cap includes an extension part on an upper circumference of a main cap that is coupled with a bottle finish of the packing-bottle containing the liquid medicine, and a cover formed on the extension part. An inside space of the cover and the extension part defines an accommodating part for accommodating the auxiliary internal medicine. Here, the accommodating part is separately provided from the main cap, and may be disposed on an auxiliary cap that is detachably coupled with the main cap. The auxiliary cap includes a skirt part forcedly fit to the main cap, an extension part formed on the skirt part, and a cover coupled to the extension part.