The invention relates to a key, in particular to a key for an optical coded lock, which is matched with the optical coded lock. The key comprises a shell, a button, a plurality of lightening holes and a lock control switch controlling device, wherein the button and the lightening holes are arranged on the shell; the lock control switch controlling device is arranged in the shell and comprises a power supply, a clock unit, a button unit, a main control unit and an LED lightening unit; the power supply, the clock unit and the button unit are respectively connected with the main control unit; the main control unit is connected with the LED lightening unit; the button on the shell is arranged corresponding to the button unit; and an LED lamp on the LED lightening unit is matched with a plurality of lightening holes on the shell. The invention has the beneficial effect that the key unlocks through remote control by one button and has convenient use, and solves the problems in the prior art that a long code needs to be input once for unlocking every time, is too fussy and easy to forget, and is especially inconvenient for old people and children to use.