A review of the boiling process in low gravity environment is presented. The data base for two-phase gas-liquid thermohydraulics in low gravity environment, in general, is relatively meager and the process is currently being studied vigorously. There exist at the present time a reasonable amount of data on adiabatic two-phase flow in low gravity environment which could allow for the development of reasonable working theoretical models. The data for two-phase flow with phase change, such as boiling, is less prevalent. The two fundamental modes of boiling in low gravity namely, pool boiling, and flow boiling, are reviewed in here. The major characteristics of low gravity pool boiling is the formation of a single large bubble at the heating surface. This bubble appears to feed on the smaller bubbles that are continuously being generated at nucleation sites along the heating surface. The bubble continues to grow with subsequent heating until it covers the entire heating surface. Also, the high heat flux in the nucleate boiling regime of the boiling curve is lower in low gravity environment than under terrestrial conditions. On the other hand, the flow boiling process in low gravity environment is much less understood. In general, the three major heat transfer regimes in flow boiling namely, the bubbly, slug, and annular flow regimes, all are characterized by having larger bubbles. In the flow quench analogy for flow boiling, a new flow regime have been found to exist in low gravity environment, which is otherwise absent under terrestrial conditions. This flow regime is characterized by having long liquid filaments embeded in the vapor and flowing along the axial direction of the tube.