A display device and a control method therefor are disclosed. According to the disclosure, the display device comprises: a sensor for sensing the surrounding environmental state; an inputter for receiving a user command for content conversion; an outputter for outputting content corresponding to the user command; and a processor for controlling the outputter such that screen brightness and/or audio output strength of second content corresponding to the user command is changed and outputted, when the user command is inputted, on the basis of the sensed surrounding environmental state and/or output information of currently outputted first content. Therefore, the display device can variously output an output of content image and/or audio according to the surrounding environmental state.