Recombinant DNA hybridizing specifically to a 300 nucleotide repeat DNA sequence (BLUR8) of human specificity and to human repeat DNA sequence (pHY10) on the Y chromosome was used for human identification and sex determination of degraded DNA samples of blood stains, dental pulp, and bone marrow. This radioactive technique enabled reliable and sensitive human and sex determination from blood stains that were more than 80 years old. Less than 1 piece of 0.5 cm length thread of blood stain was enough for both tests. DNA from relatively fresh dental pulp and bone marrow was clearly identified. The human identification test, which could recognize up to 0.3 ng DNA correctly, was 3 to 5 times more sensitive than the sex determination test.