The temperature and strain sensing property of a grapefruit microstructure fiber (MF) Bragg grating with multi-reflection peaks have been studied. Analysis indicates that the wavelength shift of this grating changes quadratically with the environmental temperature. Experimental results show that different reflection p eaks have their individual temperature sensitivities. Furthermore, the relations hip between the wavelength shifts and temperature variation has been fitted, whi ch confirms the above analysis. However, theoretical analysis indicates that the wavelength shift have a good linear relationship with the strain change. The re lationship between the wavelength shift and strain changes has been fitted throu gh experiment. The inconsistent sensitivity of different reflection peaks for th is grating ensures its practical applications in the field of multi-parameter se nsing measurement.