CPE coupled with GFAAS can attain detection limits that are up to 100 times lower compared with respective FAAS configuration [19]. In this paper, a CPE method based on the complex of Mn(II) and Fe(III) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP, its structure is shown in Fig. 1), which forms complexes with more than 40 metal ions and has found numerous applications in trace element separation and preconcentration by solvent extraction [35,36] and solid phase extraction [37,38], and using p-octylpolyethyleneglycolphenylether (Triton X-100) as surfactant is proposed for the preconcentration of Mn(II) and Fe(III) in water samples prior to their determination by GFAAS.