Abstract: In the square chart of nuclides with parameters of S=2Z-N,H=N-Z, it shows constant 44 for stable region of nuclides. Upper limits of even Z=60～82 is ΔH=2,4,8, and upper limits of even K(=S-H)=12～-8 and lower limits of even Z=80～52 are ΔH=2,2,4,4,8,8 respectively. The left limits of stable region connected with three central points are the nuclides of 703020Zn4010, 1164828Cd6820, 1927636HT5Os11640. The new fundamental law is 1,2,4,8,16,8,4,2,1 for distribution of stable isotopes. The new law by model of nucleus is made up of deuteron and triton in which with 2 of splitting and degeneracy of energy levels. Base limiting law of stable scope, it is infered that upper limiting coordinates H=60 or 80 and S=68 probably.