Provided is a vial cap for which, when there is a possibility that a cover which covers the stopper of a vial has come off and the stopper portion of the vial has been contaminated at a stage prior to use, said fact can be easily recognized. The present invention is a resin vial cap (1) that is fitted on the mouth (72) of a vial (70) in order to fix a stopper (74) that has been fitted into the mouth (72) so that the stopper will not come out of the mouth (72). The vial cap (1) is provided with a cap body (8) in which an upper opening (6) is formed and a cover (40) for covering the upper opening (6) of the cap body (8). Multiple pin-receiving holes (10) are formed in the cap body (8) and the cover (40) has multiple fixing pins (46). The respective pin-receiving holes (10) and the fixing pins (46) that form pairs with the pin-receiving holes (10) are formed in complementary shapes. The cap body (8) and the cover (40) are joined with the pin-receiving holes (10) engaged with the fixing pins (46) as a result of the multiple fixing pins (46) of the cover (40) being accommodated in the multiple pin-receiving holes (10) of the cap body (8).Mevcut buluş bir ilaç şişesi başlığı (1) ile ilgilidir. Bir tapayı (74), tapa (74) ağız bölümünden (72) düşemeyecek şekilde ağız bölümüne (72) sabitlemek için bir ilaç şişesinin (70) ağız bölümüne (72) takılan bir reçineden yapılmış ilaç şişesi başlığı (1), bir başlık ana gövdesi (8) ve bir kapaktan (40) oluşur.