This paper presents the results of research aiming at uncovering provincial CO₂ emissions patterns in China, providing insights on CO₂ emissions growth in the transportation sector, and using as case to study the low-carbon pilot region of Liaoning. We performed an energy consumption analysis, a decomposition analysis, and a decoupling analysis to provide a holistic picture of transportation-related CO₂ emissions growth over the last two decades, in parallel with the four stages of the national Chinese economic and social development plan, or “Five-Year Plan” (FYP). The results indicate that the CO₂ emissions generated by the transportation sector in the Liaoning Province have been gradually increasing from the 9^th FYP to the 12^th FYP. Economic growth and population scale proved to be positive driving factors of CO₂ emission changes. Specifically, the economic scale played the most significant role in increasing CO₂ emissions. At the same time, energy intensity served as the principal factor in curbing CO₂ emissions, while energy structure displayed relatively weaker effects. In the period investigated, the decoupling relationships have mainly experienced a clear positive trend, from an expansive negative decoupling towards a weak decoupling. Several suggestions are provided for local authorities to achieve CO₂ emissions mitigation and sustainable development in transportation sector.