The second observation of hemoglobin Pyrogos is reported. This abnormality was initially described in a Greek family, in our case it concerns an African negro originating from the Republic of Mali. The abnormal hemoglobin was without clinical or hematological consequences. The structural defect is a substitution of an Asp for a Gly in the immediate vicinity of lysine beta 82. This leads to a large inhibition of the corresponding tryptic cleavage and therefore to difficulties in the determination of the mutation. A second feature is a slight modification occurring near one of the 2.3 DPG binding site. As a consequence, the regulatory effect of this organic phosphate is smaller in the purified and stripped component than on hemoglobin A.