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Cytogenetic and molecular markers (isozymes and DNA) techniques are very important to monitor the genetic stability of the material obtained by in vitro culture, because in many occasions the micropropagated plants usually produce non-normal regenerating plants or somaclonal variants of the origin cultivars. The aim of this work was to evaluate the genetic stability of banana (Musa spp.) plants of the 'FHIA-18' (AAAB) clone obtained in vitro. The cytogenetic, isoenzymatic and RAPD analyses were carried out in plants at the late acclimatization phase and in vitro propagated with brassinosteroids analogues (Biobras-6-ABr) or oligogalacturonides mixture with polymerization grade between 9 and 16 (Pectimorf-mOLG). Plants cultured in vitro without ABr or mOLG treatment, but either under indolebutyric acid (IBA), indole acetic acid (IAA) or 6-bencyl aminopurine (6-BAP), were used as controls, and field-grown mother plants of this cultivar. Two additional treatments were also used, one applied to plants cultured in vitro under ABr during all the developmental phases, and the other one under mOLG. The results showed that the ABr and mOLG did not induce genetic variability in the regenerants obtained, remaining constant the chromosomes number of the specie (2n = 4x = 44). Twenty-nine bands were obtained with the isozymes and twenty-seven with RAPD, all monomorphic.