<i>Fusarium</i> root rot is an increasingly severe problem in soybean cultivation. Although several <i>Fusarium</i> species have been reported to infect soybean roots in Heilongjiang province, their frequency and aggressiveness have not been systematically quantified in the region. This study aimed to investigate the diversity and distribution of <i>Fusarium</i> species that cause soybean root rot in Heilongjiang province over two years. A total of 485 isolates belonging to nine <i>Fusarium</i> species were identified, with <i>F. oxysporum</i> and <i>F. solani</i> being the most prevalent. Pot experiments were conducted to examine the relative aggressiveness of different <i>Fusarium</i> species on soybean roots, revealing that <i>F. oxysporum</i> and <i>F. solani</i> were the most aggressive pathogens, causing the most severe root rot symptoms. The study also assessed the susceptibility of different soybean cultivars to <i>Fusarium</i> root rot caused by <i>F. oxysporum</i> and <i>F. solani</i>. The results indicated that the soybean cultivar DN51 exhibited the most resistance to both pathogens, indicating that it may possess genetic traits that make it less susceptible to <i>Fusarium</i> root rot. These findings provide valuable insights into the diversity and distribution of <i>Fusarium</i> species that cause soybean root rot and could facilitate the development of effective management strategies for this disease.