A review of the progress of Probabilistic Tsunami Hazard Analysis (PTHA) for mega thrust subduction earthquakes after the 2004 Indian Ocean tsunami is presented. PTHA is used to quantify the tsunami inundation characteristics probabilistically, analogous to Probabilistic Seismic Hazard Analysis (PSHA) popularized since the early 1970s. The process of PTHA is briefly presented from frequency-intensity modeling, geometric fault parameter modeling, and synthetic slip distribution modeling. There are mainly three different approaches, i.e. historical records, a logic tree and random phase, to generate different slip distributions in PTHA. PTHA is useful for risk assessment, when combined with fragility models for probabilistic damage assessment. Moreover, PTHA provides a consistent framework that allows it to be integrated with probabilistic seismic hazard analysis (PSHA) for multi-hazard damage assessment.