The differences of transformation behavior between Ni rich TiNi shape memory film (SMF) and shape memory alloy (SMA) age treated at 773 K after solution treatment at 973 K have been investigated, using Ti 51.5Ni thin film and Ti 51.5Ni bulk alloy as examples, by differential scanning calorimetry (DSC), SEM and EDX. It is found that the age treated Ni rich TiNi SMF and SMA are of the same types of transformation, i.e., A→R→M (during cooling), and M→A (during heating) ( A : parent phase; R : R phase; M : martensite); the transformation temperature of the TiNi SMF is lower than that of the SMA, but the SMFs hysteresis is larger. The transformation heat of the TiNi SMF and SMA is nearly the same. The reason that TiNi SMFs strain is sensitive to temperature is not hysteresis, but its thickness is thinner, and the temperature is easy to distribute homogeneously. The differences of transformation behavior between Ni rich TiNi shape memory film (SMF) and shape memory alloy (SMA) age treated at 773 K after solution treatment at 973 K have been investigated, using Ti 51.5 Ni thin film and Ti 51.5 Ni bulk alloy as examples, by differential scanning calorimetry (DSC), SEM and EDX. It is found that the age treated Ni rich TiNi SMF and SMA are of the same types of transformation, ie, A → R → M (during cooling), and M → A: during heating (A: parent phase; R: R phase; M: martensite); the transformation temperature of the TiNi SMF is lower than that of the SMA, but the SMF s hysteresis is larger. The transformation heat of the The reason that TiNi SMF s strain is sensitive to temperature is not hysteresis, but its thickness is thinner, and the temperature is easy to distribute homogeneously.