Predictive genetic testing for cancer allows identification of those with the mutation (mutation positive) who should undergo cancer surveillance aiming at early detection of cancer and those without the mutation (mutation negative), whose unnecessary worry can be alleviated and who need not undergo frequent surveillance. However, there is a risk that predictive testing might have a harmful emotional impact on an individual. In the course of a predictive genetic testing protocol, we assessed general anxiety (by the State-Trait Anxiety Inventory [STAI]), fear of cancer and death, satisfaction with life and attitude to the future using a questionnaire survey in 271 individuals tested for hereditary non-polyposis colorectal cancer (HNPCC). Measurements were made before the first counseling (baseline), at the test disclosure session (STAI only) and 1 and 12 months after disclosure. Although at every measurement, the mutation-positive individuals were more afraid of cancer than those who were mutation negative, in both groups fear of cancer decreased significantly from baseline after disclosure. The mutation-positive subjects were more anxious than their counterparts immediately after the test disclosure, but the differences had disappeared at the follow-ups. In other variables, neither differences between the groups defined by mutation status nor changes with time were detected. Our findings suggest that counseling and testing relieve fear of cancer; no harmful emotional impact was detectable at the 1-year follow-up. To confirm these findings, however, the impact of testing should be studied after a longer interval. Furthermore, to evaluate the ultimate interpretation of these results, studies are needed to investigate the impact of fear of cancer on surveillance behavior among the mutation-positive subjects.