Six oxygenated and oxynitrided glasses in the Ca-Si-Al-O-N system were prepared from pure lime, silica, alumina and aluminium nitride. Their enthalpies were measured by drop enthalpimetry with a Calvet calorimeter in a 100–1000° temperature range including glass transitionsTg. Their heat capacityCp in glassy and liquid states were deduced by derivation. TheCp variations atTg were calculated. The glass transition temperature were checked by differential calorimetric analysis.