Nano sheets and flower-like particles of nickel tartrate were synthesized through water-ethanol-ammonia liquid phase precipitation system. Flower-like particles of metal Ni were prepared by the thermal decomposition process, using flower-like nickel tartrate particles as precursor in an atmosphere of CO2, at temperatures of 380 °C and 420 °C, respectively. The characteristics of products were tested by means of the infrared spectrometer (IR), the differential scanning calorimeter and thermo-gravimetric analyzer (DSC-TG), the X-ray diffraction (XRD), and the scanning electron microscope (SEM). The IR studies indicate that the product is pure hydrated nickel tartrate. The studies of DSC-TG indicated that there are 2.5 moles of H2O in one mole of nickel tartrate. The analysis of XRD indicates that the silvery white powder is pure metal Ni, which has face-centered cubic crystal structure. The SEM images show that the size of the flower-like nickel tartrate particles is approximately 40 μm, and the thickness of the nano-petals is about 0.1 μm. The size of the flower-like metal Ni particles is approximately 10 μm, and thickness of the nano-petals is about 0.3 μm.