A test strip is revealed. The test strip includes a detection area, at least one outer sampling area, and a circuit system. The detection area includes a sampling hole, at least one sampling channel corresponding to the sampling hole, and at least one reaction area in the sampling channel. An inner sampling area is disposed around the sampling hole and an inner sampling opening is on an edge of the inner sampling area for communicating with the sampling channel and the sampling hole. The outer sampling area is located on an outer side of the test strip. The outer sampling area includes an outer sampling opening in communication with the sampling channel. The circuit system is electrically connected to the reaction area. The test strip further includes at least one pressing part located around the sampling hole for pressing against a test area and preventing cross-infection.