Although some knowledges about the fatigue deformation mechanisms of fee alloy single crystals containing precipitates have been obtained in the past several decades, few relevant research findings have been reported on precipitates containing bee alloy single crystals. In the present work, a single-slip-oriented bee Fe-35%Cr alloy (mass fraction) single crystal containing Cr-rich precipitates was prepared as the target material, and its fatigue deformation features were investigated under constant plastic strain amplitude control. Experimental results and analyses demonstrate that, when the plastic strain amplitude epsilon(pl) >= 2.5 x 10(-3), the Cr-rich precipitates can be readily sheared by the moving dislocations during deformation, leading to an obvious stress softening phenomenon observed at the tensile loading stage of the first cycle, and subsequently to a slight cyclic softening phenomenon at a very early stage of cycling. In addition, the tension-compression stress asymmetry was found c during cyclic deformation of the crystals, and this enhanced stress asymmetry should be related to the deformation instability of Cr-rich precipitates. The slip deformation features were mainly manifested by the formation of coarse slip bands comprising a quantity of fine slip lines and also by the formation of the kink band at high epsilon(pl) (e.g., 5.0 x 10(-3)). The primary crack develops roughly along the primary slip plane ((1) over bar 01) and the crystal finally cracks along this plane, accompanied with some secondary cracks having various morphologies being formed on the crystal surface. Microstructural observations indicate that persistent slip band (PSB) ladder-like structures can be found at a low epsilon(pl) of 5.0x 10(-4), and the volume fraction of them increases with increasing epsilon(pl). As epsilon(pl) is raised to 5.0x 10(-3), the microstructural features are primarily characterized by the formation of dislocation cells.