If a person holds two different valid ID cards, it is undoubtedly an illegal act. The information on the ID card is unique and fixed, especially the ID card number. An individual can only hold a valid ID card. With a new ID card, the old one is invalid.
[Legal Basis]
Article 16 of the Identity Card Law states that anyone who commits one of the following acts shall be given a warning by the public security organ and imposed a fine of not more than 200 yuan. Any illegal gains, if any, shall be confiscated:
（1） Obtaining a resident identity card by using false certification materials;
（2） Renting, lending or transferring resident identity cards;
（3） Illegally detaining another person's resident identity card.
