In order to improve the corrosion resistance of LA141 magnesium-lithium alloy,the surface of LA141 magnesium-lithium alloy with a thickness of 3 mm was treated with phytic acid chemical conversion by orthogonal experiment.The self-corrosion current density of different process parameters of phytic acid chemical conversion was studied by electrochemical workstation.The effects of concentration of phytic acid chemical conversion solution,treatment time and pH value on the corrosion resistance of LA141 magnesium-lithium alloy were discussed.The optimum parameters of phytic acid chemical conversion were obtained by optimization.The results show that the influence of process parameters on phytic acid chemical conversion of LA141 magnesium lithium alloy is pH value ＞ conversion time ＞ concentration of conversion solution.When the phytic acid concentration is 20 g/L,the conversion time is 10 min and the pH value is 6,the corrosion resistance of LA141 magnesium lithium alloy after phytic acid chemical conversion is the best.At this time,the self-corrosion current density is the minimum,which is 2.818×10－5A/cm2.Compared with that before phytic acid conversion,the self corrosion current density decreases by one order of magnitude,and the corrosion resistance is greatly improved.Phytic acid chemical conversion can improve the corrosion resistance of LA141 magnesium lithium alloy,which has some reference for the surface corrosion protection of other magnesium lithium alloys.