Volumetric analysis, gravimetric analysis, spectrophotometry and polarography of iron were investigated from the point of view of sensibility, accuracy, precision and procedure. As a result, it was found that volumetric analysis was reliable and easy in procedure but was not suitable for micro analysis. On the other hand, gravimetric analysis was lacking in rapidity. Farther, spectrophotometry and polarography were good methods for ultramicro analysis but were unsatisfactory in reliability.