In coping with climate change, China's CO2 mitigation targets should keep in step with the achievement of the long-term goal of holding temperature increase to well below 2 degrees C above pre-industrial levels by the end of this century (this is referred to as the 2 degrees C goal). Many previous papers have highlighted the implications of different effort-sharing principles and schemes in determining national contributions to global mitigations. In this paper, China's energy transformation towards the 2 degrees C goal until 2100 is examined in an integrated-assessment model in light of different effort-sharing principles to understand how the application of such schemes may alter China's energy system transformation on a pathway to this long-term goal. Across scenarios, China's non-fossil energy will account for 50-70% and 85% of primary energy consumption in 2050 and 2100, respectively in the scenarios in this study. Fossil energy with carbon capture and storage technologies and non-fossil energy will dominate power generation in China over the long run. Coal will be phased out in end-use sectors and electricity use will expand regardless of the effort-sharing principles. The sensitivity analysis of long-term steady-state levels implies that the ultimate level that emissions could reach will have great influences on the energy system transformation in China.