To provide a disassembling device easily carried into a site by providing a base mounted with a clamp section, a wrench section, and a driving means.

A clamp section 10, a wrench section 20, and a driving means 30 are mounted on a base 40. The driving means 30 gives the rotation around the axis to the wrench section 20 when a handle lever is reciprocated, and it is provided with a wrench cylinder reciprocating the handle lever and an oil pressure generating device feeding pressure oil to the wrench cylinder. The oil pressure generating device is provided with a power converting mechanism converting the rotation of a motor into the reciprocating motion of an oil pressure generating piston. A connecting member is intermittently rotated around the axis by the wrench section 20, and it is twisted and disassembled from a rod member.