Abstract: The method of ridge estimation to treat ill-posed and weighted total least squares adjustment(TLSA) is put forward.The solution equation and evaluating precision by mean square error are deduced.The model parameter discernable matrix in ill-posed and weighted TLSA is defined,then the meaning and effect of the ridge parameter is discussed.For the case that the ridge parameter is difficult to determine in ridge estimation to treat ill-posed and weighted TLSA,the L-curve method,generalized cross-validation(GCV) and the ridge mark method are introduced and given.At last,through some cases,the comparisons are carried out among the L-curve method,GCV and the ridge mark method,also the results of common least squares(LS) and total least squares are given,and some conclusions are obtained.