To improve the corrosion resistance of FeMnSi based shape memory alloy, a newly developed Fe-11Mn-5Si-9Cr-5Ni-10Co shape memory alloy with good shape memory effect (SME) and excellent corrosion resistance was investigated in this paper. Immersion test showed that the weight loss rate is about 0.0011 [g/m(2)h] after exposed in the sea air for six months, which is comparable to HDR stainless steel. By solution at 700degreesC followed by thermo-mechanical training, the shape recovery ratio was 80% under 5% pre-deformation. The stress-induced fcc-->hcp martensitic transformation of the shape memory alloy (SMA) was studied by high voltage transmission electron microscopy (TEM), The results have showed that there are more stacking faults in Co bearing SMA than that in Co free SMA. Based on the TEM observation on the microstructure of the annealed alloy at different temperatures, it is suggested that uniform distribution of the orientated stacking faults in the parent phase is favorable to obtain excellent shape memory effect.