  Presented are complete electroweak (EW) corrections at ${\cal
O}(\alpha\alpha_{\mathrm s}^{\mathrm 2})$ to top-squark pair production at the
Large Hadron Collider (LHC) within the framework of the Minimal Supersymmetric
Standard Model (MSSM). At this order, effects from the interference of EW and
QCD contributions have to be taken into account. Also photon-induced top-squark
production is considered as additionnal partonic channel which arises from the
non-zero photon density in the proton. Furthermore, the impact of MSSM
parameters on the EW corrections is analyzed.
