Cork oak decline has been a serious problem in Portuguese central and southern areas in the last 30 years. This decline is associated with Phytophthora cinnamomi, a pathogen with a major impact on cork oak decline. A programme aiming the plant selection on resistance, to address the infection of soilborne P. cinnamomi in cork oak woodlands, should therefore be fundamental for an integrated strategy for the management of the cork oak woodlands. In this context, the main objective of this study was to select potential tolerant families by evaluation of field susceptibility to the pathogen. During 10 years (2004–2014), the survival and height growth of 157 cork oak families from eight different provenances from Portugal and Spain were assessed in a field highly infested with P. cinnamomi. Results showed a high mortality of the plants, over the whole period, insofar that only 14 families, out of the 157, showed a survival rate between 40% and 60%. These families exhibited also a good height growth with heights ranging between 1 and 1.50 m. It was also observed that ploughing, leading to better soil conditions, could contribute to improve the survival rate and the development of plants. Potential families of cork oak were identified as tolerant plant material and rootstock, thereby candidates to be used in restoration and reforestation. Interestingly, additional results concerning a Quercus faginea family evidenced a good resistance of this species to the pathogen. This information is indicative that Q. faginea could be used as a rootstock for the cork oak reforestation in areas where the pathogen had high impact.