A connection structure of display panel and system circuit is provided. The disclosure also provides a liquid display panel and a liquid display device. The connection structure includes an array substrate, a printed circuit board, and a plurality of electrically conductive particles. The array substrate provides a plurality of signal lines in a display portion thereof and provides a plurality of traces in a fan-out portion thereof. The signal lines at least includes a first signal line and a second signal line at different height layers. The traces at least includes a first trace and a second trace at different height layers. One end of each trace is electrically connected with one signal line, and the other end of each trace is electrically connected with one conductive line via electrically conductive particles.