Background: Silicosis refers to a spectrum of pulmonary diseases attributed to inhalation of free crystalline silicon dioxide. It entails inflammatory response in which Interleukin-1 alpha is a key mediator. Objectives: to evaluate the role of interleukin-1α (IL-1α) as a biochemical marker for detection of pulmonary toxic effects of silica in relation to clinical and radiological manifestations among exposed workers. Methods: The study was conducted on 64 male workers exposed to silica dust assigned to El-Harareyat Factory of Alexandria. An interviewing questionnaire was used to collect data about personal, occupational and medical characteristics. Pulmonary function testing, plain chest radiographs and laboratory assessment of serum level of IL-1α were done for all workers. IL-1α was assessed also among a matched control group. Results: Prevalence of silicosis was 37.5%. Serum IL-1α level among silica-exposed workers was 2.8±1.8 pg/ml while it was undetected among a control group of healthy males. IL-1α was positively correlated with wheezes, negatively correlated with FVC, FEV1, MMEF, FEF_50%, positively correlated with extent of nodular opacities in lung zones and presence of enlarged and calcified hilar lymph nodes. Conclusion: IL-1α can be a good monitoring marker for the earliest sign of silicosis; hilar lymphadenopathy.