The invention discloses a hand-operated rock core cutting device. The hand-operated rock core cutting device comprises a base, wherein the base comprises a baseplate, a supporting seat head is arranged at each of the two ends of the baseplate, a pair of movable slide bars arranged parallelly are arranged between the supporting seat heads, a sliding convex block is arranged on the movable slide bars, a cutter head convex block and a hand shank are rotationally arranged on the sliding convex block, and a rotatablecutting disc is arranged at the bottom of the cutter head convex block; the sliding convex block comprises a pair of sliding through holes and a pair of movable through holes, the movable slide bars penetrate through the sliding through holes, and the cutter head convex block is connected with the movable through holes through a movable pin bolt. According to the hand-operated rock core cutting device, the hand-operated static pressure cutting is totally adopted, so that power sources are not required, and the cutting device is particularly suitable for field application; meanwhile, the small-sized cutting disc is adopted, so that the damage to the body of the rock core can be prevented.