The present invention relates to a formation device of ridges on rice paddies, more preferably a formation device of ridges on rice paddies which is capable of simply forming the ridges preventing water inside the rice paddies from flowing out by being formed on one side of the rice paddies on the proceeding direction of a tractor, using a rotation forming unit in a cone shape expanding regardless of a linear section or a curved section. The formation device of the ridges on the rice paddies comprises the following: a ridging device (10) installed on a tractor or a cultivator； an ascending and descending unit (20) installed on the outer surface of an ascending and descending stand (11) protruding from one side of the ridging device to be ascended and descend to the vertical direction； a rotary shaft (30) combined to the ascending and descending unit (20) to be rotated； a power transfer shaft (31) transferring power of a motor by being combined to the rotary shaft (30)； an elastic spring supporting cylinder (50) combined to the ascending and descending unit (20) for supporting one end of the rotary shaft (30) by installing an elastic spring (40) on the outer circumference of the rotary shaft (30)； a sliding cylinder (60) inserted to the outer circumference of the elastic spring supporting cylinder (50) for supporting the other end of the elastic spring (40), and sliding to left and right sides by elastic force of the elastic spring (40)； a connection rod (70) extended from the end of the rotary shaft (30)； and the rotation forming unit (80) in a cone shape including an insertion groove (81) in the inside to be integrated to the connection rod (70) and rotating the connection rod (70).본 발명은 논두렁 조성장치에 관한 것으로, 더욱 바람직하게는 트랙터 진행방향의 전답 일측으로 형성되어 논에 가둔 물이 새어나가지 않게 하는 논두렁을 직선구간이나 곡선구간에 관계없이 신축작용을 하는 고깔형의 회전 성형구에 의해 간단하게 성형할 수 있도록 하기 위한 것이다.그 구성은 경운기나 트랙터에 장착되는 배토기(10)와, 상기 배토기(10)의 일측면에 수직으로 돌출하여 형성된 승하강대(11)의 외주면에 장착하여 상하로 승하강하는 승하강구(20)와, 상기 승하강구(20)와 결합되어 회전하는 회전축(30)과,
