Pulmonary ThromboEmolism (PTE) is an important disease for legal medicine. Because of their sudden lethal onset, generally medicolegal autopsies show few clinical information when PTE is the cause of death. During medicolegal autopsies, the autopsy operator must answer to important questions. For example, autopsy operator can need to assess the casual relationship between PTE and recent accident, such as trauma or long air travel. Furthermore, the autopsy operator needs to investigate the pathology of PTE as a cause of sudden cardiovascular death. It is relatively simple to confirm a fatal massive thromboembolus in the initial stage of thoracic investigations, but sometimes it might be difficult to distinguish this from postmortem clot. In such cases histopathological examination can help in the differentiation. Histological examination is also required for observation of chronological changes of the thrombi. Chronological evaluation is an important factor especially to determine whether the death coincides with the date of a specific accident/event or instead there is an earlier onset of PTE. In addition, histological sections sometimes show additional information, such as tumor fragments in cases of malignancy or small fragments of bone marrow in cases of active resuscitation, that can be useful in a medicolegal scenario. Furthermore, new diagnostic tools are arising, which they can be very helpful in the individuation of this frequently underdiagnosed disease. The goal of our work is to investigate these aspects through the review of the recent literature.