SummaryGenomic DNA from 81 isolates ofGremmeniella abietinacollected from eleven plantations each ofPinus sylvestrisandPinus contortain northern Sweden was studied using RAPD markers. The DNA variation between and within populations and the race and type distribution ofG. abietinapopulations, causing symptoms similar to those of the North American race, were studied. The degree of genetic similarity was greater amongG. abietinaisolates from the same geographical areas than among isolates from different geographical areas, regardless of whether they were isolated fromP. sylvestrisorP. contorta. RAPD variation was greatest in the central parts of northern Sweden, suggesting that sexual reproduction has been somewhat more important there than further north or south. Only the RAPD fragments characteristic of the EU race ofG. abietinawere found in the material tested. The RAPD pattern described as characteristic of the northern type within the EU race was identified in 62% of the isolates. Divergence from the expected profile was due to differences in occurrence of fragments OPA12‐1400 and 12‐1500. This indicates that this part of the RAPD profile cannot be treated as diagnostic for the northern type. A conclusion of practical importance is that there is a considerable risk ofG. abietinaspreading from infectedP. contortaplantations to adjacent areas with indigenousP. sylvestrisregeneration, and vice versa, owing to the indicated lack of host‐specificity of the pathogen. It is possible, however, that host‐specific strains exist, but do not differ in their RAPD p