The utility model provides a moisture content of wood automatic measurement device, relates to the forestry engineering field, including timber storehouse, conveyer belt and test tape, the side in timber storehouse be provided with the dodge gate, dodge gate upset is downwards opened, the conveyer belt on evenly distributed be fixed with the rubber slab, the width of rubber slab equals the width of timber sample, the interval of two block adjacent rubber slabs is greater than the width of timber sample, the test tape on evenly distributed have water ratio tester, two adjacent water ratio tester's interval equals the interval of two blocks of adjacent rubber slabs. The utility model discloses a rubber slab replaces the narrow banding shift fork among the prior art, and at the timber sample in -process that delivers from godown, the rubber slab can provide stable flat support for lower timber sample that is about to to deliver from godown, compares with the shift fork among the prior art, and the area of contact the during support has increased, and the holding power distributes on the holding surface, so the probability greatly reduced of timber sample fish tail.