Objective To investigate the relationship between second-hand smoke exposure and lung cancer death trend in Huizhou area. Methods The corresponding records of lung cancer in the tumor registration system in Huizhou area from January 2019 to December 2019 were collected to investigate the subjects' second-hand smoke exposure. Linear regression model was used to analyze the correlation between the mortality of lung cancer patients and the second-hand smoke exposure rate. Logistic regression model was used to analyze the correlation between second-hand smoke exposure and death of lung cancer patients. Results In 2019, the mortality rate of lung cancer patients in Huizhou was the highest in the third quarter, and the second-hand smoke exposure rate of lung cancer patients was also the highest in the third quarter. The mortality rate of lung cancer patients in Huizhou was significantly positively correlated with the second-hand smoke exposure rate (r2 = 0.985 9, P<0.05). The second-hand smoke exposure rate, second-hand smoke exposure concentration, and the extent of second-hand smoke environmental enclosure of dead cancer patients were significantly higher than those of lung cancer patients in the survival group, and the difference was statistically significant (P<0.05). The second-hand smoke exposure, second-hand smoke concentration and the extent of the enclosure of second-hand smoke environment were independent risk factors influencing the death of lung cancer patients (P<0.05). Conclusion The trend of lung cancer deaths in Huizhou in 2019 was consistent with the prevalence of second-hand smoke exposure. The second-hand smoke exposure is an important factor for lung cancer deaths.