The molten pool temperature of laser deposition shaping titanium alloy was measured by using infrared thermometer real-time tracking measurement method, the effect of process parameters and scanning path on both molten pool temperature and layer size during metal laser deposition forming was researched. The results show that, with the laser power and powder feeding rate increasing, the molten pool temperature,height and width of parts becomes larger;as the scanning speed increasing, the temperature of the molten pool decreases, height and width of parts becomes smaller.Forming height is directly affected by temperature gradient which is affected by different scanning routes; The change reason of both molten pool temperature and layer size was analyzed base on energy input. These results would provide the guidance for optimizing process parameters and scanning path base of the real-time infrared detection molten pool temperature to improve the forming quality.