The invention relates to a cable trench cover opening technology, in particular to a mechanical lifting appliance for cable trench covers of a substation and a switching station. The invention solves the problem that the conventional cable trench cover opening technology is easy to cause the effects that sealing performance of the cable trench cover becomes poor, time and labor are wasted and the cable trench cover is easy to cause accidental damage to a constructor. The mechanical lifting appliance for the cable trench covers of the substation and the switching station comprises a bracket part and a lifting part; the lifting part comprises a Z-shaped crank, chains, lifting hooks and three-jaw suckers; the upper end of a first chain is wound and fixed at a first horizontal edge of the Z-shaped crank; a first lifting hook is fixedly arranged at the lower end of the first chain; the middle part of a second chain is hung on the first lifting hook; a second lifting hook and a third lifting hook are respectively fixedly arranged at both ends of a second chain; handles of two three-jaw suckers are respectively hung to the second lifting hook and the third lifting hook. The mechanical lifting appliance is suitable for opening the cable trench covers.