The semaphorin family consists of a set of secreted and transmembrane proteins which contain a domain of approximately 500 amino acids called the semaphorin domain. The investigation of the role of semaphorin proteins in the nervous system has established them as chemorepellents of axons. Recent studies have identified the semaphorin proteins on the surface of cells in the immune system and in the genomes of two lytic viruses. These strongly suggest the possible involvement of the semaphorin proteins in the immune system. This study aims to understand the expression patterns of four semaphorin genes, Sema3B, Sema4A, Sema4F, and Sema6C in the lymphoid tissues of wild type mice. These proteins were chosen to represent the three subfamilies III, IV, and VI. The first family contains secreted proteins which have immunoglobulin domains (III), the second contains transmembrane proteins which have immunoglobulin domains (IV), and the third contains transmembrane proteins which do not have immunoglobulin domains (VI).