Cleistanthus collinus is a poisonous plant as they required special treatment for their safety measure for collection and preservation by herbarium specimen. Aryl naphthalene has numerous physiological activities and it is present in plant. The present investigations focus for solid-liquid extraction of plant which extract derivative of lignan by soxhlet extractor method. Optimization of types of solvents with respect to polarity alcoholic extract and defated petroleum ether has effective solvent. Quantification of solvent volume for extracting compounds from plant (1gm per 15 ml). Determination of effective time for respective solvent for extraction.