The requirements for applying for a Ph.D. degree in Princeton University mainly include the academic background, experience and personal characteristics of the applicant, as well as materials that can prove the applicant's strong interest in the applied subject.

First of all, the doctoral application of Princeton University requires the applicant to obtain an academic degree from a first-class overseas university, and has a strong academic background and research experience in the application field. Secondly, applicants need to submit resumes, letters of recommendation and academic papers to prove their academic ability and enthusiasm for academic fields. In addition, applicants also need to submit GRE (green test) transcripts and other documents provided by Princeton University. Finally, applicants need to attend graduate interviews to prove their academic potential and ability.

Princeton University has strict requirements for doctoral application, and applicants need to be prepared in research background and academic literacy to ensure the success of the application.