This article presents a review of current data on genetic mapping of pea (Pisum sativum L.) genes participating in development and regulation of arbuscular-mycorrhizal and legume-Rhizobial symbioses. By means of mutational analysis several regulatory symbiotic genes (Sym-genes) were identified in model and crop legumes, particularly, among them more than 40 pea Sym-genes. Some of them are already cloned and sequenced, and structural and functional similarity was demonstrated for orthologous Sym-genes in different legume species. The functions of these genes are diverse and include the control of perception of the microsymbiont's signal molecules, activation of the signal cascade (which is common for both legume-rhizobial and arbuscular-mycorrhizal symbioses), and consequent transcriptional changes in root cortex. To identify the sequence of mutated pea genes, an approach is used that is based on comparative genetic mapping and search for candidate gene in the genome of closely related legume plant barrel medic (Medicago truncatula Gaertn.). The web site www.phytozome.net (D.M. Goodstein et al., 2012) presents the current state of the barrel medic's genome sequencing in the form of genome browser, which facilitates the search for homologous genes and the sequence analysis of candidate genes. Significant similarity of pea and barrel medic genomes allows development of gene-based molecular markers, comparison of obtained pea genetic map with M. truncatula genome, and pea gene cloning after finding mutations with similar phenotypic manifestation. Currently, most of pea Sym-genes are mapped in genome; that resulted in identification of the sequences of 14 symbiotic genes. In particular, authors of the present review were able to sequence the pea genes Sym35 - the homologue of NIN of Lotus japonicus (Regel.) K. Larsen (A.Y. Borisov et al., 2003), Sym37 - the homologue of NFR1 of L. japonicus (V.A. Zhukov et al., 2008), Sym33 - the homologue of IPD3 of barrel medic (E. Ovchinnikova et al., 2011), Cochleata - the homologue of NOOT of barrel medic (J.M. Couzigou et al., 2012). In recent years, considering the development of modern technologies of Next Generation Sequencing and massive genotyping, an avalanche of data on mapping pea gene-based data is being accumulated. Saturation of pea genetic map with markers, undoubtedly, will facilitate mapping of symbiotic genes and identification of their sequences; this will help to broaden the understanding of how the system of genes, which control interactions with beneficial soil microorganisms, functions in pea.