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Superoxide dismutases (SODs) belong to the group of metalloenzymes that remove superoxide anion radicals and they have been identified in three domains of life: <i>Bacteria</i>, <i>Archaea</i> and <i>Eucarya</i>. SODs in <i>Synechocystis</i> sp. PCC 6803, <i>Gloeobacter violaceus</i> CCALA 979, and <i>Geitlerinema</i> sp. ZHR1A were investigated. We hypothesized that iron (FeSOD) and/or manganese (MnSOD) dominate as active forms in these cyanobacteria. Activity staining and three different spectroscopic methods of SOD activity bands excised from the gels were used to identify a suitable metal in the separated samples. FeSODs or enzymes belonging to the Fe-MnSOD superfamily were detected. The spectroscopic analyses showed that only Fe is present in the SOD activity bands. We found FeSOD in <i>Synechocystis</i> sp. PCC 6803 while two forms in <i>G. violaceus</i> and <i>Geitlerinema</i> sp. ZHR1A: FeSOD1 and FeSOD2 were present. However, no active Cu/ZnSODs were identified in <i>G. violaceus</i> and <i>Geitlerinema</i> sp. ZHR1A. We have shown that selected spectroscopic techniques can be complementary to the commonly used method of staining for SOD activity in a gel. Furthermore, the occurrence of active SODs in the cyanobacteria studied is also discussed in the context of SOD evolution in oxyphotrophs.