Recent advances in the study on the mass balance of Antarctic Ice Sheet show that the West Antarctic Ice Sheet exhibits a bimodal behavior, with thickening in the west and more rapid thinning to the north, but is probably losing mass overall at a rate sufficient to raise sea level by almost 0.2 mm·a -1 . The East Antarctic Ice Sheet seems to be close to balance, but it is still impossible to determine even the sign of its mass balance. The state of Antarctic Ice Sheet mass balance is still unknown at present. Meanwhile, stoppage of huge glaciers, acceleration of others, rapid thinning of large sectors of ice sheet, rapid breakup of vast areas of ice shelf and acceleration of tributary glaciers, and vigorous bottom melting near grounding lines show substantial changes on relatively short time scales are commonplace on Antarctic Ice Sheet. The following key future research fields are needed to understand and predict Antarctic Ice Sheet mass balance: Observation and modeling of the surface elevation changes, determination of surface mass balance and its distribution over drainage basins as well as fluxes at the grounding lines and the bottom melting underneath ice shelves, understanding of the deglaciation history, development, comparison and improvement of all kinds of models related to modeling and prediction of ice sheet mass balance.