The invention provides an automatic bolt connecting device for a steel arch frame and a bolt installation method and relates to the technical field of automatic bolt connecting devices. Through the automatic bolt connecting device for the steel arch frame and the bolt installation method, the technical problems that the connecting efficiency is low and the connecting labor intensity is large due to the fact that steel parts to be connected in a steel arch frame are connected through bolts through manual operation in the prior art are solved. The automatic bolt connecting device comprises a bolt containing mechanism, a bolt clamping and tightening mechanism and a driving mechanism. The bolt containing mechanism can contain bolts. The driving mechanism can drive the bolt clamping and tightening mechanism to move. The bolt clamping and tightening mechanism can clamp the bolt when moving to the location below the bolt containing mechanism. The bolt clamping and tightening mechanism can enable the clamped bolt to be aligned with a bolt hole in the connection position and tighten the bolt into the bolt hole when located in the location below the connection position of the two steel partsto be connected. The automatic bolt connecting device is used for improving the connecting efficiency of the steel arch frame and reduce the labor intensity.