Foundation pit supporting device facilitating subsequent construction of foundation pit

The utility model discloses a foundation pit supporting device convenient for follow-up construction of a foundation pit, and aims to provide a foundation pit supporting device which can bear vertical load of a profile steel inner supporting beam so as to prevent the middle part of the profile steel inner supporting beam from bending downwards under the action of self weight; and a foundation pit supporting device used for supporting a stand column pile of the profile steel inner supporting beam in the foundation pit can be omitted. The structure comprises a structural steel inner supporting beam, a structural steel outer supporting beam and a structural steel inner supporting beam, the bracket device comprises two profile steel brackets located at the same height and a connecting longitudinal beam connecting the two profile steel brackets, the two profile steel brackets are arranged on the foundation pit fender posts, bracket supporting faces are arranged on the profile steel brackets, and longitudinal beam