The invention discloses a mobile terminal editing input method and a mobile terminal editing input system. The method comprises the following steps: 1, obtaining a maximum line number M which is allowed to be input by an existing editing frame, and monitoring whether the input content exceeds the maximum line number M which is allowed to be input; 2, if the monitored input content exceeds the maximum line number M which is allowed to be input, popping a suspended editing frame on a mobile terminal display interface, and putting and displaying the monitored input content in the suspended editing frame; 3, after ending the editing of the input content, clicking a sending button on the suspended editing frame to send; or after ending the editing of the input content, clicking the suspended editing frame to return to an original input interface, and clicking the sending button to send. According to the mobile terminal editing input method disclosed by the invention, the suspended editing frame is popped to paste information of any length into any editing frame and the suspended editing surface is automatically entered when the line number of the pasted or input content is recognized to exceed a threshold value, so that the operation or the preview of the sent content is very convenient. The whole process is intelligent, simple and quick, meets the needs of a user, so that the user experience is improved.