Serial extraction is a sequential plan of premature removal of one or more deciduous teeth in order to improve the alignment of permanent teeth and then removal of permanent teeth to maintain the proper ratio between tooth size and arch size. The aim of this case report was to present a case treated successfully with a modified serial extraction protocol in the lower arch because the patient had congenitally missing lower second premolars with severe crowding. The treatment consisted of selective removal of the deciduous mandibular teeth only (C, D, and E) and no permanent premolar removal. However, the space of the missing second premolars was utilized to resolve the anterior crowding along with the spontaneous closure of the extra spaces by physiologic movement of the permanent mandibular teeth. Whereas in the upper arch conventional serial extraction was performed.