The present invention relates to a kind of injection devices. The injection device includes: main body, and to keep injection tube, injection tube has the needle extended from one end With the lid for being removably attachable to main body. Covering has the needle shield for covering the needle. Injection device further comprises biasing member and lock. Biasing member is configured to drive at least part of lid to leave main body. Lock can change in lock state and unlocked state, and in lock state, lock keeps together lid and main body, and in unlocked state, lid and main body can be moved apart.
