Overview of top quark physics at the ep colliders

In this talk we present a short overview of top physics at the electron-proton (ep) colliders. Currently, the proposed ep collider is the Large Hadron Electron Collider (LHeC), which is a combination of 60 GeV electron beam and 7 TeV proton beam of the LHC tunnel. This may be extended to Future Circular electron-hadron Collider (FCC-eh), which features a 60 GeV (or higher) electron beam with the 50 TeV proton beam from the Future Circular hadron Collider (FCC-hh). Selected topics include but not limited to top structure function, top parton distribution functions, top spin polarization, top electric charge, measurement of $\rm V_{tb}$, anomalous $\rm tt\gamma$, ttZ, tbW, $\rm tq\gamma$, tqH couplings and CP phase of ttH coupling.