Abstract: The main deficiencies of the traditional initial orbit determination with space-based angle measurements are due to that the systematic error observation data and the coefficient matrix is ill-posed or singular. Based on the analyses,the semi-parametric regression model of observation equations was established. The general regularization least squares estimation method based on penalized least squares estimation and ridge estimation was deduced,and the correlative characteristics of the method was proved. To improve the calculating efficiency,the column pivot element Givens-QR decomposition algorithm was introduced. Experimental computation indicates that the method is effective in achieving a satisfying result.