Abstract: AlSi7Mg aluminum alloy specimens were die casted with different pouring temperatures and die preheating temperatures, and the mechanical properties of the specimens were tested and X-ray nondestructive analysis was carried out.The results are as follows: when the pouring temperature is 700℃, with the increase of the die preheating temperature from 150℃to 350℃, the strength of the test piece first increases and then decreases.The tensile strength of the specimen with the die preheating temperature of 250℃reaches the maximum value of 240.74 MPa, and the yield strength is 182.71 MPa.When the die preheating temperature is 250℃, the strength of the specimen also shows a trend of increasing first and then decreasing as the pouring temperature increases from 680℃to 720℃.Under the same conditions of other die-casting parameters, no obvious defects are observed in the X-ray non-destructive testing of AlSi7Mg aluminum alloy die-casting specimens poured at 700 ℃when the die preheating temperature is 250℃.