For the first time, in the Fe-16Mn-10Cr-8Ni-4Si (wt.%) alloy single crystals with a reversible FCC↔HCP martensitic transformation (MT), oriented for tension along the [111] direction, a shape memory effect (SME) of 10 % was obtained with a successive increase in strain in the "load-unloading" cycle and heating in a free state. The magnitude of the SME turned out to be close to the theoretical value of the transformation strain ε_tr=10.8 % for FCC-HCP MT in this orientation under tension. The physical reason for achieving the SME close to the theoretical value of ε_tr is associated with a high level of stresses at the yield point σ_0.1 of the initial FCC phase, which leads to the development of FCC↔HCP MT under stress without defect formation. Keywords: single crystals, FCC-HCP martensitic transformation, shape memory effect, tension