The invention discloses a washing machine and a control method for a child lock thereof. The method comprises the steps of (S1) receiving a child lock signal; (S2) monitoring whether a door cover of the washing machine is opened or not in real time, if so, executing the step (S3); (S3) detecting that the door cover opening time reaches set time, and controlling the washing machine to drain away water; (S4) completing draining and controlling automatic power-off of the washing machine. After the washing machine enters the child lock function, all keys on an operation panel are locked, misoperation of a child is prevented from affecting normal operation of the washing machine or generating a risk; the washing machine is capable of carrying out alarm prompting and timely discharging the water in a barrel when opening the cover in the running process of the washing machine, thereby preventing the child from entering the barrel to cause a risk.