Certain techniques fundamental to the study of algebra. One of such techniquesrnis the construction of a quotient set of an algebraic structure by arnmeans of an equivalence relation on the given set. Based on this, we constructrna quotient subtraction algebra, which plays a crucial role in the studyrnof algebra. In this project work, we will introduce the notion of subtractionrnalgebra, which is an algebraic structure on a set with a binary operation,rnusually called subtraction. To define subtraction algebra, we use the thernconcept of equivalence relation, subtraction algebra and ideal of subtractionrnalgebra to define a quotient subtraction algebras and study its properties.rnThe idea of isomorphism theorems of other algebraic structures is used torndefine isomorphism theorems of quotient subtraction algebras.