Abstract: Some adjustable parameters are added to the general many-knot spline,a new kind of interpolating curve is constructed.At control points,we can control the tangent vectors of fitting curve by adjusting these parameters,and the better fitting result can be obtained.The scheme retains the advantages of common many-knot spline （cardinal-type,local-property）,it can help engineers in CAGD applications to design and locally adjust the fitting curve.