In this study, high resolution (40 Hz) sea levels derived from the advanced SARAL/AltiKa satellite altimetry are validated over the Southeast Asia coastal regions. The parameter of sea level is derived based on three standard retracking algorithms of MLE-4, Ice-1, and Ice-2. The assessments of quantity and quality of the retracked sea levels are conducted to identify the optimum retracker over the study regions, which are the Andaman Sea, the Strait of Malacca, the South China Sea, the Gulf of Thailand, and the Sulu Sea. The quantitative analysis involves the computation of percentage of data availability and the minimum distance of sea level anomaly (SLA) to the coastline. The qualitative analysis involves the absolute validation with tide gauge. In general, AltiKa measurement can get as close as ~1 km to the coastline with ≥85% data availability. The Ice-1 retracker has shown an excellent performance with percentage of data availability ≥90% and minimum distance as close as 0.9 km to the coastline. In term of quality of the data, 3 out of 6 validation site show that Ice-1 retracker is superior than the other retracker with temporal correlation up to 0.89 and RMS error up to 8 cm.