The submarine gas pipeline from Ghana's Jubilee oilfield to gas treatment plant as Ghana's first submarine gas pipeline is of great significance to the improvement of Ghana's domestic energy structure and relief of domestic power supply shortage. Due to technical issues such as rich heavy hydrocarbon in gas composition, the diameter of submarine pipeline varying from DN 250 to DN 300 and large dropping variance and so on, common methods for submarine pipeline start-up are not applicable. Simultaneous operation of drainage, drying and start-up has been realized successfully by selecting pig properly, optimizing drainaing scheme, which provides experiences for the start-up of deep-sea submarine pipeline.