The comparison of wet digestion and microwave digestion of Cd, Co, Cr,Cu, Mn, Pb, Zn, Fe, and Ni contents of the river bottom and sea floor sedi-ments from the various locations of Turkey was performed in the presentwork. After digestions, the heavy metal concentrations were determinedby flame atomic absorption spectrometry (FAAS). The heating programsfor microwave digestion, different combinations, and volumes of acidmixtures were evaluated for microwave digestion efficiency.