Lemierre syndrome, also known as postpharyngeal septicemia or necrobacillosis, is a rare and fatal opportunistic infection, often caused by the bacterium Fusobacterium necrophorum that enters the throat. A common method of diagnosis is bacterial culture, but it can be time-consuming and insensitive. Next-generation metagenomic sequencing (mNGS) represents an emerging technique for the detection of infectious diseases. This method enables a quick and accurate diagnosis of Lemierre's syndrome by obtaining accurate information about the source of the infection. The authors of the article present the case of a patient with Lemierre syndrome, who was quickly and accurately diagnosed by mNGS. mNGS thus becomes an important complementary method for rapid treatment.