In the following, we summarize the specific requirements for admission :

Admission to the Doctoral Schools is open to candidates of any age and citizenship holding an Italian “Diploma di Laurea” awarded according to the university rules prior to Ministerial Decree no. 509/99 or a “Laurea Specialistica” awarded according to Ministerial Decree no. 509/99 or a “Laurea magistrale” awarded according to Ministerial Decree no. 270/04 (please see “Requisiti di partecipazione” indicated for each school).

Foreign degree:

An equivalent foreign degree of equivalent duration and content which has been previously recognized by the competent Academic Bodies of an Italian University, including degrees awarded in the context of interuniversity cooperation and mobility programmes. In the case of foreign degrees, instead of the graduation date, the candidate must indicate when and by which Italian University the degree was recognised as equivalent to an Italian degree. By the time a successful candidate wishes to enrol, if the recognition of a degree has not been officially confirmed , the School’s Academic Board will deliberate upon recognition of the degree, with specific reference to the admission to the course.

a short written description of the candidate's research interests and possible future research objectives.
https://www.unisi.it/ricerca/dottorati-di-ricerca/informazioni-dottorandi-e-dottori-di-ricerca