The effects of betatizing and aging temperatures on the martensitic transformation characteristics in an Cu-13.4wt%Al-4.2wt%Ni single crystal have been studied. Microstructures show that the specimen betatized above $800^{circ}C$ has only ${{eta}_1}^{prime}$ martensite while the specimen betatized of below $700^{circ}C$ has two phases i.e., ${{eta}_1}^{prime}+{gamma}_2$ When betatizing temperature increase from $600^{circ}C$ upto $900^{circ}C$, Ms and As temperatures decrease due to the dissolution of which ${gamma}_2$ phase depletes Al content in the matrix thereafter makes the both Ms and As temperatures significantly increased. Ms and As temperatures of the specimen aged at $200^{circ}C$ are relatively stable but those of the specimen aged at $300^{circ}C$ are shifted rapidly with aging time, especially within the first 30min.