In cases of disguising handwriting or documents, it refers to the suspect intentionally changing their writing habits and methods through improper means to obtain a certain document in order to achieve a certain benefit. Therefore, in practical work, it is difficult to verify and identify disguised handwriting and documents, which delays the investigation and litigation of cases. In order to better investigate cases of disguised handwriting and documents, psychological testing techniques are used to conduct psychological tests on the parties involved in such cases, in order to determine who is the creator of the disguised handwriting and documents.