The present invention relates to steel plate for making submarine pipeline and its rolling process. The steel plate has the chemical components including C 0.030-0.075 wt%, Si 0.10-0.30 wt%, Mn 1.40-1.60 wt%, P not more than 0.015 wt%, S not more than 0.003 wt%, Cu not more than 0.20 wt%, Ni 0.10-0.25 wt%, Mo 0.07-0.20 wt%, Nb 0.03-0.05 wt%, V not more than 0.060 wt%, Ti 0.001-0.02 wt%, Al 0.01-0.06 wt%, Cr not more than 0.20 wt%, N not more than 0.009 wt%, Ca 0.001-0.005 wt%, B not more than 0.0005 wt%, Sn not more than 0.010 wt%, As not more than 0.030 wt%, and Fe for the rest. The steel plate has high cleanliness, high strength and high toughness, and is used in producing submerged arc welded submarine pipeline.