The most commonly used method for determining the specific heat capacity is the Differential Scanning Calorimetry (DSC). This measuring device enables continuous measurements of the specific heat capacity over a large temperature range with short analysis times. All cp-measurements in this thesis were performed on a heat flux DSC (type: Netzsch DSC404 Pegasus F1) by the standardized sapphire method according to ASTM E1269-11. Through an own method improvement the best measurement settings have been determined to analyse steels up to high temperatures. Thereby the performed measurements achieved a combined measurement uncertainty of 1.7% or 0.012J/(g*K) at 600°C, 2.5% at 800°C or 5.4% at 1000°C. In the practical part cp-measurement of selected binary Fe-Si, -Al, -Mn model alloys and various industrial alloys were performed up to 1050°C and compared with ThermoCalc (TCFE7) and FactSage (SGTE2014). The single-phase regions (ferrite or austenite) of the binary alloys are very well described by the thermodynamic programs. Thermodynamic calculations correspond in the single-phase regions with pig iron, as well as with the alloys TRIP, TWIP, HS2-9-1-8, X40CrMoV5-1 and X15CrNiSi25-20. The largest deviations of 10 to 20% are observed within the austenitic steel X1CrNiMoCuN20-18-7 and the valve steel (1.4882).