Eco-linguistics is a young branch of linguistics.It is the study of interrelationships of language and ecology.Sociolinguistics is also a new interdisciplinary subject,which is the study of interrelationships of language and social structure,linguistic variation.In this paper,these two subjects will be compared. Eco-linguistics is a young branch of linguistics. It is the study of interrelationships of language and ecology. Sociolinguistics is also a new interdisciplinary subject, which is the study of interrelationships of language and social structure, linguistic variation. In this paper, these two subjects will be compared.