Nitrogen content is a property of asphalts that have not received the attention that its importance merits. Asphalt chemistry often is considered an extension of hydrocarbon chemistry and the characteristics that are associated with the low boiling fractions of petroleum are assumed to be slightly modified for asphalt. Asphalt however, is composed essentially of hydrocarbon c0ompounds containing sulfur, oxygen and nitrogen. This paper shows the importance of the nitrogen content through development of three concepts: 1) Most of the nitrogen in petroleum is fond in the asphaltic fractions. Some asphaltenes contain as much as an average of tw0-atoms of nitrogen per molecule. 2) Nitrogen not only forms an integral part of the high molecular weight compounds, but is so firmly combined that upon pyrolysis, most of the nitrogen remains in the coke. 3) Nitrogen and consequently asphalt has significance geochemically as an indication of the degree of maturation or age of an oil.