Photographic properties of cobalt (III), copper (II) and palladium (II) malonato complexes were studied by measuring photographic sensitivities and spectral sensitivities. The results were compared to those of the corresponding oxalato complexes. It was shown that malonato complexes were less sensitive than the corresponding oxalato complexes. The most sensitive among the complexes studied here was potassium dioxalato palladium (II), followed by oxalatodiamino palladium (II). These two complexes also showed the largest amplification of sensitivity when thermally developed. Spectral sensitivities of malonato complexes are similar to those of oxalato complexes found in literatures. The mechanisms of photolysis and pyrolysis were studied to identify the image compounds by measuring infrared and reflection spectra and differential scanning calorimetry curves (DSC). It was found that cobalt (III) malonato complex was reduced to cobalt (II) complex and palladium (II) malonato complex decomposed probably to metal or oxide.