Manufacturing companies operating within the high-technology sector are of interest to science, industry and national authorities because of the special economic importance attached to them. However, in order to investigate the condition of those companies, support their growth and monitor the effects of the aid awarded to them, it is first necessary to properly identify the business entities belonging to that sector. To identify the entities belonging to the high-technology industry, it is necessary to perform a sequence of activities which form the procedural algorithm. Usefulness of the algorithm has been verified using the example of a group of Warsaw high-tech companies which were subject to investigation under the European project Warsaw Entrepreneurship Forum. The algorithm could be used as the basis for the implementation of an IT tool for the identification and description of high-tech businesses.