Abstract: Disclosed are nickel-based amorphous alloy compositions, and particularly quaternary nickel-based amorphous alloy compositions containing nickel, zirconium and titanium as main constituent elements and additive Si or P, the quaternary nickel-zirconium-titanium-silicon alloy compositions comprising nickel in the range of 45 to 63 atomic %, zirconium plus titanium in the range of 32 to 48 atomic % and silicon in the range of 1 to 11 atomic %, and being represented by the general formula: Nia(Zr1−xTix)bSic. Also, at least one kind of element selected from the group consisting of V, Cr, Mn, Cu, Co, W, Sn, Mo, Y, C, B, P, Al can be added to the alloy compositions in the range of content of 2 to 15 atomic %. The quaternary nickel-zirconium-titanium-phosphorus alloy compositions comprising nickel in the range of 50 to 62 atomic %, zirconium plus titanium in the range of 33 to 46 atomic % and phosphorus in the range of 3 to 8 atomic %, and being represented by the general formula: Nid(Zr1−yTiy)ePf.