DNA fingerprinting or DNA profiling is becoming a new method of identification that analyses and compares fragments of DNA from separation on independent sources. It is an immensely useful and powerful method of such investigation is based on the premise of comparison of a sample collected from the crime scene and another from the accused. It means that police always need second sources for comparison to already known DNA fingerprint developed from the sample recovered from the place of occurrence. The DNA finger printing is based on the principle that complete DNA of each individual is distinct. DNA or genetic finger printing is the only definitive positive and permanent identification method of a person as one’s DNA neither changes during one’s life time nor it can be altered by any method. The samples to carry out DNA finger printings are obtained from the trace amount of blood, semen or vaginal smear, buccal smear and hair, nail of skin cells. DNA Technology has been proved to be a boon for innocent suspects, investigating agencies and judges and bane for real culprits whether alive or dead. In several cases DNA came to rescue the innocent convicts by post-conviction DNA tests.