Based on the analysis of the X-ray diffraction data of liquid Al and Sn, temperature-induced structural transformations are found for liquid Al in the range of 1050—1250℃ and for liquid Sn near 800 and 1200℃. The nearest neighbor distance r1 of Al and Sn decreases with the increase of temperature. The structure of liquid Sn is similar to α-Sn on the short-range order length scale. The physical meaning of the correlation radius rc is discussed.