The invention discloses a washing processing unit and a control method of the washing processing unit. The washing processing unit includes the following sections: a grounding line; a control section for determining whether the grounding line is connected to the external grounding terminal; and a display section for displaying whether it is grounding. In the present invention, the user can confirm whether the washing processing unit is grounding or not, in order to prevent the electric shock phenomenon of users caused by leakage current.