Abstract: A new kind of technology called mechanical vapour compression (MVC) is proposed for the feed water treatment process for boiler used in offshore heavy oil thermal recovery. The characteristics of this new technology are analyzed, such as treated water quality, energy consumption, maintenance cost and area covered, also, the new technology is compared with reverse osmosis (RO) technology. From the analysis results, compared with RO technology, the new technology can tolerate feed water of worse quality, total dissolved solid (TDS) of its treated water is less than 5 mg/L, and the area covered of new technology can reduce by more than 20% with less maintenance cost. However, the cost of MVC itself and energy consumption of this technology are high, and need to be localized. Through analysis, it is proved that MVC technology can be used in oilfield produced water recycling process for boiler used in offshore heavy oil thermal recovery. In conclusion, in the situation of offshore heavy oil thermal recovery, MVC can be used in feed water treatment process for boiler, and its application prospect is very broad.