Using the two theoretical schemes incorporating the bond parametric function and sizefactor proposed by one of the authors (ZBW), we have studied successfully the solid solubilities of thebinary alloys based on the 2 3 transition metals, 18 simple metals, 1 2 rare earth metals and 3 actinide Manuscript received on Apr4, 1994 Guest Professor of International Centre for Materials Physics, Academia Sinica, Shenyang, 110015 metals, respectively in past ten years. The theoretical results for the 3864 alloys based on 56 metals aresummarized and the theoretical model are systematized in this paper. It has been found that the quantitative equation for separating the soluble elements from the insoluble elements is a parabola oran ellipse (x￣2-m)￣2/c￣2+(y_2-n)￣2/d￣2=1 for every host metal, whatever the metal is located at which period in the period table. The constants a and b in the parabola equation, and m, n, c and d in the ellipse e-quation have heen discussed, which can be related to some appropriate parameters for each host metalrespectively. The results show that the overall reliabilities of the solid solubilities for the 3864 binary alloys based on the 56 metals are 87.2% and 90.3% for the parabola and ellipse regularities respectively,which indicates that this theoretical description of solid solubilitles and its results are rarely seen in theliterature before both in the systematization of study and in the agreement between the theoretical results and experimental data.