Marx Theory was named after Marx, which was the constant viewpoint of Engels and which is because Marx was the main creator of Marx Theory. We should not deny Engels contribution to the establishment of Marx Theory while we admit that Marx is the main creator of Marx Theory. Engels did unique theoretical contribution to the establishment of Marx Theory. Engels is an usher of the establishment of Marx Theory, is a discoverer of the philosophy of materialism, is a participator and accomplisher of Marx political and economic theory creation and is a founder of scientific socialism.