During the period between March 1987 and July 1988 the authors examined for the presence of Campylobacter pylori bioptic specimens from the gastroduodenum from 410 patients. In the above group they diagnosed by microscopic examination C. pylori in 257 patients (mean 63%). From the whole group 282 patients (100%) were examined concurrently by the microscopic method and by cultivation. This number comprised 195 (68.9%) who were positive on microscopic examination and 110 (42.2%) who were positive on cultivation. A microaerophil medium was obtained by using Gas Pak H2 + CO2 envelopes (Oxoid) and envelopes generating gases H2 + CO2 (JZD Dukla Drahany) without a catalyst and a gas mixture of 85% N2, 10% CO2 and 5% O2. The best detection rate was obtained in basic medium for blood agar no. 4 (Imuna) with 7% ram blood in a defined gas mixture (92%). When investigating the survival of C. pylori in specimens kept in 20% glucose in a refrigerator for 20 or more hours after collection of the sample, the microbe was isolated (from 27 microscopically positive samples) from 19 patients, i.e. 51.2%.