Objective: The purpose of this study is to find a new way to operating and improving the usability of touch interface when remotely controlling a PC through a tablet PC.<BR>Background: With the recent activation of telecommunication due to the coronavirus situation, remote control has become a widely accepted telecommunication tool. However, since existing operation methods for remote control via a touch screen often cause dissatisfactions to the user, there is a need for better touch interfaces.<BR>Method: Two new operation methods, which are distinct from two operation methods being provided in existing applications, are devised in the research. Next, under the condition of remote control, data search, data verification, and data transmission procedures were assumed and executed through an experiment. Finally, an optimal alternative was found through analyses.<BR>Results: When using a tablet PC to remotely control a PC, the gamepad mode was most preferred over other operation methods for double-clicking and scrolling. However, since there is no drag or drop function possible in gamepad mode, the touch button method was the most preferred for drag and drop since of touch interface. Statistical analysis shows that while there are differences in task completion time depending on display size, virtual keyboards are the most efficient way to operate when double-clicking and scrolling. Next, the touch button is an efficient operation method, and the touch mode and trackpad are less usable. Drag and drop function does not differ between touch mode and touch button, but the trackpad is less usable.<BR>Conclusion: In order to increase the usability of a tablet PC during remote control, a newly devised auxiliary operation method was proposed and yielded a better performance than currently available methods in terms of improving the usability. <BR>Application: This study is expected to be applied to smartphones as well as tablet PCs, as it aims at changing existing operating methods and eliciting improvements in remote control of PCs with touch screens.