An easy-sampling geological sample sampling mechanism comprises a dynamic spiral drill bit device (5) for drilling a sample in a slit (10) in a geological body (1) and a fixing machine frame (2) fixedly mounted on the geological body (1), wherein the upper side of the dynamic spiral drill bit device (5) is fixedly connected with the lower end of a lifting driving external thread component (44); external threads are arranged on the outer circumferential surface of the lifting driving external thread component (44), and are matched with internal threads in a gear thread component (41) rotatably mounted inside the fixing machine frame (2) and driven by a driving gear (43); an axially stretching sliding slot (40) is formed in the inner circumferential surface of the lifting driving external thread component (44), and is axially slidably and circumferentially fixedly matched with a radial stretching part (35) fixedly connected with the lower end of a connecting rod (34) capable of running through the inner cavity of the lifting driving external thread component (44).