Method and device for measuring equivalent density while drilling

The invention discloses a method and device for measuring equivalent drilling fluid density while drilling, which is capable of measuring annular pressure while drilling, automatically tracking drilling depth and borehole path downhole, monitoring drilling fluid equivalent density and change thereof in real time, judging whether the equivalent density is within an allowed security window range, mastering conditions of downhole pressure control, borehole cleaning, formation fluid immersion and the like in time, effectively guiding the drilling technical personnel to perform construction and preventing downhole complex conditions and accidents, thereby safely and smoothly reaching the formation of interest by drilling, and realizing reservoir protection and other expected well drilling targets.