Fixing structure, substrate unit, and flexible substrate unit

A fixing structure of a flexible substrate and a connection substrate, the fixing structure comprising:

• a housing that is fixed to the flexible substrate in such a way that contact points of the flexible substrate are exposed;
• a lock claw fixed to the housing;
• a cage that is fixed to the connection substrate so as to cover contact points of the connection substrate, the housing being capable of being inserted and removed into and from the cage in a direction parallel to a surface on which the contact points of the connection substrate are disposed;
• a lock hole which is formed in the cage and with which the lock claw is engaged in a state in which the housing is inserted into the cage;
• and
• a pushing part that is fixed to the housing or the cage and pushes the housing toward the connection substrate in the state in which the housing is inserted into the cage.