The present invention provides shuffled playing cards which eliminate the need for a game host to shuffle cards before games by taking a lot of time as well as eliminate the possibility of cheating. A shuffled playing cards (1) obtained by shuffling a predetermined number of decks of playing cards (12) using a shuffling machine is packaged as an individual pack. The shuffled playing cards (1) is individually packaged and sealed with an adhesive label (13). A bar code (13a) which represents a unique shuffled card ID has been printed on the adhesive label (13). The shuffled card ID is registered in a database by being associated with information which allows identification of a shuffling machine used to shuffle the playing card set.