This study investigates the association between oral microbiota dysbiosis and oral cavity cancer. Patients with primary oral cavity cancer were compared to healthy controls in terms of oral health, socio-demographic factors, and microbial composition. The results show that oral cavity cancer patients had poorer oral health, with more signs of gingival bleeding, swelling, and redness. Microbiological analysis revealed significant differences in bacterial phyla and genera between the two groups. Specifically, *Proteobacteria*, *Aggregatibacter*, *Haemophilus*, and *Neisseria* decreased, while *Firmicutes*, *Bacteroidetes*, *Actinobacteria*, *Lactobacillus*, *Gemella*, and *Fusobacteria* increased. At the species level, *C. durum*, *L. unaeans*, *N. subflava*, *A. massiliensis*, and *V. dispar* were significantly lower, while *G. haemolsys* was significantly higher. Major periodontal pathogens, *P. gingivalis* and *F. nucleatum*, increased 6.5- and 2.8-fold, respectively. The study concludes that oral cavity cancer patients have a distinct oral microbiome composition influenced by personal daily habits, which may be associated with the pathogenicity of the disease. These findings suggest that oral microbiota dysbiosis could serve as a potential marker for oral cavity cancer and highlight the importance of maintaining good oral hygiene and treating periodontal disease to reduce the risk of oral cancer.This study investigates the association between oral microbiota dysbiosis and oral cavity cancer. Patients with primary oral cavity cancer were compared to healthy controls in terms of oral health, socio-demographic factors, and microbial composition. The results show that oral cavity cancer patients had poorer oral health, with more signs of gingival bleeding, swelling, and redness. Microbiological analysis revealed significant differences in bacterial phyla and genera between the two groups. Specifically, *Proteobacteria*, *Aggregatibacter*, *Haemophilus*, and *Neisseria* decreased, while *Firmicutes*, *Bacteroidetes*, *Actinobacteria*, *Lactobacillus*, *Gemella*, and *Fusobacteria* increased. At the species level, *C. durum*, *L. unaeans*, *N. subflava*, *A. massiliensis*, and *V. dispar* were significantly lower, while *G. haemolsys* was significantly higher. Major periodontal pathogens, *P. gingivalis* and *F. nucleatum*, increased 6.5- and 2.8-fold, respectively. The study concludes that oral cavity cancer patients have a distinct oral microbiome composition influenced by personal daily habits, which may be associated with the pathogenicity of the disease. These findings suggest that oral microbiota dysbiosis could serve as a potential marker for oral cavity cancer and highlight the importance of maintaining good oral hygiene and treating periodontal disease to reduce the risk of oral cancer.