Well-head safety operation ladder

The utility model relates to a combine ladder, in particular to a safety working ladder used at well mouth for installation, maintenance and low pressure test-drilling of oil production field. The technical proposal is: the utility model comprises a master ladder, an assistant ladder, an extension ladder and an operation platform; wherein, the master ladder and the assistant ladder form a trestle ladder, the master ladder and the extension ladder form an elevating ladder with the extension ladder which is provided with pulley and ropes which are connected with a hook hidden within the master ladder; the operating platform is foldable and is movably connected with the joint part of the master ladder and the assistant ladder. The utility model has the advantages of: three-ladder-in-one with the trestle ladder, the straight ladder and the elevating ladder organically combined or used separately, the utility model can be uses as a well mouth special ladder or a common ladder. The utility model can be uses to climb or to hoist and is with small size and is easy to carry. The utility model greatly reduces the labor intensity of assembly, improves work efficiency and eliminates hidden trouble.