The effects of adding Cr on the transformation and the low temperature deformation characteristics in the deformed plus annealed Ti-Ni shape memory alloy (SMA) were investigated by differential scanning calorimetry and tensile test. The results show that after adding trace Cr, the R and martensite (M) transformation temperatures θR and θM decrease a lot, the M transformation temperature hysteresis ΔθM increases, the platform-stress σM in the stress-strain curves increases significantly, and the superelasticity (SE) improves, and the ductility deteriorates in Ti-Ni SMA. After adding trace Cr, the low-temperature SE of Ti-Ni SMA also improves greatly. At room temperature, the Ti-50.8Ni SMA shows shape memory effect (SME) + SE, while the Ti-50.8Ni-0.3Cr SMA shows SE. The annealing temperature affects low temperature deformation characteristics of Ti-Ni SMA. When deformed at 10 oC, the 400-500 oC annealed Ti-50.8Ni SMA shows SME, the 550-650 oC annealed Ti-50.8Ni SMA shows SME + SE, while the 400-650 oC annealed Ti-50.8Ni-0.3Cr SMA shows SE continuously.