Provided is a safety apparatus for a cultivator. A driving cylinder includes a body wherein a rod having a pressurizing plate at a front end of the rod is inserted into the body; a first inlet hole and a second outlet hole which are formed at one side of the body; a first inlet hole and a second outlet hole formed at a rear portion of the pressurizing plate when the rod extends from the body; a first outlet hole and a second inlet hole formed at the other side of the body; a relief valve at the first outlet hole; a first hydraulic line to connect the relief valve and the first inlet hole; a second hydraulic line to connect the second outlet hole and the second inlet hole; and a check valve at any of the second outlet hole, the second inlet hole and the second hydraulic line.