Lots of buildings settled and tilted in the disaster areas attacked by the Chi-Chi earthquake. For the damaged buildings with stable upper structure, the foundation rehabilitation was performed to recover its original function. The underpinning method and grouting method were used most commonly for the foundation rehabilitation. A total of 3 remedial cases for each remedial method were studied in this paper and the construction processes, rehabilitation effectiveness and the problem encountered during construction were investigated and evaluated. As a result, the comparison of advantage/disadvantage and applicability between two methods are proposed. Results of this study indicate as the detail investigation prior to construction and the proper construction management were conducted during rehabilitation, the damaged foundation can be retrofitted effectively within an appropriate schedule; otherwise, the effective rehabilitation can not be reached and the construction duration will be postponed. Because the local experiences of foundation rehabilitation are limited in Taiwan and some major problems do not resolved yet, it is suggested that the techniques and abilities of foundation rehabilitation should be improved by the engineers with greater efforts.