The quality of production of metallurgical bar stock, in particular tubes, is assessed based on many production parameters including outer cross-section (diameter) and ovality, which are also specified by European standard EN 13 508. Tubes need to be measured as soon as possible, ideally immediately after the rolling mill during their production, so that any defects may be corrected in due time and thus the loss of material and power may be minimized. This means that the tubes need to be measured at high temperatures (approximately 1.000 °C). The article describes a new method of non-contact measuring of outer diameters and ovality of steel tubes cross sections that meet the above-mentioned requirements and allows reliable measuring of required parameters even in the case when the measured material moves or vibrates vertically during measuring.