Background: The respiratory microbiome of lung cancer patients is different from healthy people. Finding the characteristics of microorganisms is conducive to exploring new directions for the assist in distinguishing different histological types of lung cancer. Methods: 16S rRNA sequencing and internal transcribed spacer sequencing were performed respectively on sputum samples from 8 adenocarcinomas, 10 squamous cell carcinomas, 5 small cell lung cancers, and 3 combined-small cell lung cancer patients. And then, bioinformatics analysis of their bacterial microbiome and fungal mycobiome were conducted. And the correlation between respiratory microorganisms and clinical characteristics was further analyzed.Results: The difference in species diversity of the respiratory tract microorganisms of different histological types of lung cancer is statistically significant. Moreover, smoking can increase the diversity of respiratory bacteria. Nevertheless, quitting smoking is beneficial to the transformation of the respiratory tract flora to a non-smoking state. Spearman’s correlation further showed that Fusarium was positively related to Streptococcus, Neisseria, Prevotella-7, and Veillonella, and Penicillium was positively related to Neisseria. Conclusions: Based on the differences of microorganisms among different histological types of lung cancer, deep composition characterization of lung cancer-related microorganisms and their clinical characteristics is an important advancement in understanding the role of microorganisms in lung cancer development.