Background: Gold standard method for the measurement of Magnesium is the atomic absorption spectrophotometery. Studies are shown that Magnesium concentration can also be measured by photometric assay. Therefore, the purpose of this study was to compare the two methods for Magnesium measurement in the patient’s serum.

Materials and Methods: Forty diabetic patients (10 men and 30 female) participated in this study. Mean age of the patients was 52.52±4.88. Magnesium was measured in serum by the atomic absorption spectrophotometric and photometric methods (Pars Azmun Kit, using Xylidyl Blue, wave length=546 nm) and then the results were compared.

Results: The mean values for the photometric and spectrophotometric methods were 3.03±0.82 and 3.07±0.42, respectively. No significant difference was seen between the two methods (P=0.7).

Conclusion: Considering the lower cost and accessibility of using the photometric method, this method, as a reliable method, can be recommended to measure the level of Magnesium.