There is provided a vial cap with which, when there is a possibility that a cover which covers a stopper for a vial has come off and the stopper for the vial has been contaminated at a stage prior to use, the fact can easily be recognized. The vial cap is a resin vial cap (1) to be attached to a mouth portion (72) of a vial (70) to fix a stopper (74) fitted into the mouth portion (72) so that the stopper may not come off the mouth portion (72). The vial cap (1) is provided with a cap main body (8) that has an upper opening (6) formed therein and a cover (40) that covers the upper opening (6) of the cap main body (8). The cap main body (8) has a plurality of pin-receiving holes (10) formed therein, and the cover (40) has a plurality of fixing pins (46). Each pin-receiving hole (10) and a fixing pin (46) that is paired with the pin-receiving hole (10) are formed in complementary shapes. The plurality of fixing pins (46) of the cover (40) are accommodated in the plurality of pin-receiving holes (10) of the cap main body (8), and the cap main body (8) and the cover (40) are joined with the pin-receiving holes (10) and the fixing pins (46) engaged.
