The present invention relates to producing a forward osmosis membrane by forming a nanofiber support membrane layer on a polyester nonwoven material using sulfonated polysulfone (sPSf) polymer, and by coating this sulfonated polysulfone nanofiber support membrane layer with a thin film composite of polyamide. The objective of the present invention is to realize a forward osmosis membrane production method by using sulfonated polysulfone (sPSf) polymer, which enables performance improvements in parameters such as water permeability and reverse salt passage in production of thin film composite forward osmosis membranes.