"King of Coal" - a novel written by the great American writer Upton Sinclair, reveals the problem of coal mines and the life of workers in industrial cities. In his works, the author raises questions of justice and social inequality, clearly showing the hard life of ordinary people and the ruthless attitude of the authorities towards them. "King of Coal" is not only a literary masterpiece, but also a relevant commentary on the present, which leaves a deep mark in the heart of every reader.