With　the　continuous　development　of　the　lab-on-a-chip　studies,　pressure　measurements　in　microchannels　have　become　the　guarantee　of　the　precise　control　and　regulation　of　trace　fluids　using　microfluidics　and　caused　more　research　attention.　In　this　review,　we　first　present　the　basic　principles　and　structures　of　various　pressure　measurement　methods　in　microchannels,　including　the　following:　(i)　membrane　or　diaphragm-based　methods;　(ii)　membrane-free　in-situ　methods;　(iii)　membrane-free　side-channel　methods;　and　(iv)　other　methods.　We　then　illustrate　the　key　applications　of　these　methods　in　biology,　medicine,　microfluidic　chips,　and　fluid　mechanics.　Finally,　we　prospect　the　future　developments　of　these　methods,　which　can　lead　to　an　unprecedented　capability　to　develop　more　novel　designs　of　pressure　sensors　and　further　applications.　We　aim　to　provide　a　deeper　fundamental　understanding　of　the　mechanisms　of　these　methods,　which　could　be　both　a　reference　for　pressure　measurement　method　researchers　and　a　resource　for　those　outside　this　field　who　wish　to　identify　the　most　suitable　pressure　sensor　for　a　particular　application.