The invention relates to an inner chain link compressing mould which is used for compressing an inner chain link, in particular to a manufacturing mould for an inner chain link of an escalator step chain, and belongs to the field of chain manufacturing. The inner chain link compressing mould comprises an upper mould seat which is fixed to a punching head of a punching machine and a lower mould seat which is positioned right below the upper mould seat and is fixed to a work table of the punching machine; positioning cores which are used for compressing and positioning an inner chain link are symmetrically arranged on the lower mould seat; the lower mould seat is provided with a lower mould plate; the lower part of the lower mould plate is fixedly connected with a bottom plate through bolts; guide holes which are used for guiding the positioning cores are symmetrically formed in the lower mould plate; a compression spring which is arranged on the bottom plate and corresponds to each guide hole is arranged below the corresponding positioning core. The inner chain link compressing mould has the beneficial effects that the structure is simple, the installation is convenient, the application range is wide, and the production efficiency is high.