By using the conventional observation and NCEP reanalysis data, two soaking rain processes in Heilongjiang Province from 21 to 23 and 25 to 26 April 2012 are compared. The contrast analysis of their meteorological characteristics is made from the aspects of the synoptic circulation pattern and physical mechanisms. The results show that two soaking rain processes was influenced by a low vortex. The rainfall area of the first soaking rain process was near the low vortex center; there was a uniform rainfall distribution and 3 ℃ to 5 ℃ temperature fall at 850 hPa. The rainfall of the second soaking rain process was near the shear line from the low vortex; there was a uneven rainfall distribution and 9 ℃ to 15 ℃ temperature fall at 850 hPa. The low level south west airflow provided sufficient moisture from the Yellow Sea and the Sea of Japan. Water vapor, dynamic, and thermal conditions of the second soaking rain were more favorable than those of the first soaking rain, but there was little difference in rainfall between the two processes in the western Sanjiang Plain.