This article addresses the questions such as what is meant by "Naturalism", who were the pioneer writers of 'Naturalist Movement' started in France in 1880, what does nature mean in different civilizations and religions etc? Raising all these questions, difference between mankind and civilized human being is established, it not only differentiates realism with naturalism but also throws light on the inception of Naturalist Movement in Norwegian theatre and then in French novels. Along with this, the work of the pioneer writers of Naturalist Movement is also discussed.