The major effect on respiratory health caused by chronic coal dust exposure is coal worker’s pneumoconiosis(CWP), characterized by relatively mild interstitial inflammation and fibrosis of the lungs. Coal dust is composed of carbon and other substances, including quartz and its oxides. Although coal dust is much less fibrogenic than silica, coal dust has been known to play an important role in inducing lung damage through the activation of the fibrotic process. In Korea, coal seams are mainly composed of anthracite situated between layers of granite and having a high quart contents. Different epidemiological studies reached conflicting conclusions as to whether there was a correlation between coal-dust exposure and the development of lung cancer. Telomerase is a ribonucleoprotein that synthesizes and directs the telomeric repeats onto the 3’end of existing telomeres using its RNA component as a template(Christopher et al., 1992). Telomerase activity has been shown to be expressed in immortal cells, cancer and germ cells, where it compensates for telomere shortening during DNA replication and thus stabilizes telomere length(Nam et al., 1994). To evaluate the activity of telomerase using the autopsied lungs of pneumoconiotic patients, we used the TRAP(Telomeric Repeat Amplification Protocol) assay. The purpose of this study was to investigate whether coal dust-induced pulmonary inflammation or fibrosis which could evolve into a tumor and, if so, the possible mechanism by which this might occur.