Loading machine holding fork hydraulic system

The invention relates to a loading machine holding fork hydraulic system. The problem that a holding fork is damaged by yawing force which is generated from the current loading machine holding fork during the operating process is solved. The loading machine holding fork hydraulic system comprises a left hydrocylinder, a right hydrocylinder and a multitandem valve. A multitandem valve comprises a left hydrocylinder control linkage, a right hydrocylinder control linkage, a left pilot proportional valve and a right pilot proportional valve. Two pilot oil opens of the left and the right pilot proportional valves are connected with a left and a right control ends of the left and the right hydrocylinder control linkages correspondingly. According to the loading machine holding fork hydraulic system, the stretching and clamping of an upper fork body can be harmoniously controlled, the fact that the single side of the upper fork body is deformed and damaged by the yawing force in the operating process is avoided, and