PhD in Sustainability Science

A three-year programme with an innovative approach to sustainability issues and a global change perspective.

Program Level
Programme Location
Tokyo, Japan
Program Start Date
September 2024

Applications for September 2024 entry will open in December 2023. 

This programme will equip graduates with comprehensive, multidisciplinary knowledge of sustainability problems, and deepen their understanding of the role of environmental sustainability in addressing current issues related to global change, specifically those related to climate change and biodiversity. Students undertake problem-oriented research by playing an active role in UNU-IAS research projects, and acquire the quantitative and qualitative analytical skills necessary to understand the underlying principles of various systems involved in sustainability issues and debates.

Students can select courses from those offered by UNU-IAS, while also enjoying the opportunity to take courses at other leading universities in Japan such as the University of Tokyo, Sophia University, and International Christian University.



Programme Structure & Language

The programme is offered on a full-time basis only. The standard period to complete the degree requirements is 36 months or six academic semesters, excluding time spent on study leave of absence from the university. By July of their third-year students are expected to complete all of the course requirements, obtaining at least 14 credits and completing a doctoral dissertation.

The language of instruction is English. [Top]

Admission Requirements

Applicants for the PhD in Sustainability Science are required to have met ALL of the following requirements by the application deadline in order to be considered:

1. A completed Master’s degree (or equivalent) from a recognised university or institution of higher education in a field related to sustainability in accordance with the UNU-IAS thematic areas, and a minimum of 2 years of professional field experience related to UNU-IAS research themes which was acquired after obtaining a university degree (full time equivalent);


1. Two completed Master’s degrees, at least one of which must be in a discipline related to sustainability studies (those who expect to receive a second Master’s degree before the entrance period of September 2023 may also apply);

2. A GPA of 2.8 or above on a 4.0 scale (equivalent to 70% on a 100 % scale) for at least one of the Master’s degrees earned; and

3. English language proficiency.

The minimum score requirements for English language qualifications required by UNU-IAS are:

  • 600 on TOEFL – Paper-Based Testing (PBT) OR
  • 100 on TOEFL – Internet-Based Testing (IBT) OR
  • 7.0 on IELTS – Academic format

* Please note that TOEFL and ILTS test scores are valid for two years. Invalid test scores will not be accepted. IELTS Indicator (7.0 and above) and TOEFL iBT Home Edition (100 and above) may be accepted for those who reside in a country where either IELTS or TOEFL test services are not provided due to the COVID-19 pandemic.

UNU-IAS requires original TOEFL/IELTS score reports (no photocopies accepted).

  • TOEFL: Please order an official score report using the institution code 6991. For more information on TOEFL, please visit
  • IELTS: Please request that an official report be sent directly to UNU-IAS. For more information on IELTS, please visit
  • IELTS Indicator (7.0 and above) and TOEFL iBT Home Edition (100 and above) may be accepted for those who reside in a country where either IELTS or TOEFL test services are not provided due to the COVID-19 pandemic. [Top]


  • Application Processing Fee: None
  • Tuition Fee: USD 10,000 per year*

To secure admission, successful applicants will be required to pay at least 50% of the tuition fee for the first academic year (USD 5,000*, non-refundablewithin 10 UNU working days** after the result announcement and prior to enrolment. Students who choose to pay annually must pay a full one-year tuition payment before the commencement of the academic year. Successful applicants are required to submit all documents and pay the tuition fee by the deadline.

The estimated total expenses for living and studying in Tokyo for 3 years are approximately USD 84,000, including tuition. Applicants must ensure adequate financial resources to meet the full costs of educational and living expenses.

* The fee is subject to change.
** UNU holidays can be found in Resources for Students. [Top]

Joint Diploma Programmes

Students of the UNU-IAS doctoral degree programme are also encouraged to pursue one of two joint diplomas in sustainability science, which are offered in partnership with the University of Tokyo Graduate School of Frontier Sciences (UT-GSFS), and with Sophia University. These diploma programmes require students to gain 18 credits, of which eight must be from courses specified by UNU-IAS and the partner university under the respective joint diploma programme. A joint diploma can only be awarded to students who successfully complete the two-year UNU-IAS master’s degree programme. [Top]

Japan Foundation for UNU (jfUNU) Scholarship

The scholarship is competitive and may be awarded to eligible students who have been accepted for enrolment in the PhD programme. There is no separate application form for the scholarship as it is part of the main online application form for admission. Interested applicants must provide the necessary information and documents for the scholarship when applying to the PhD programme.

I. Coverage

The jfUNU scholarship provides a monthly allowance of 120,000 JPY as a support package for a maximum of 36 months. The tuition fees may be waived for the scholarship recipients.

II. Eligibility Requirements

Applicants must meet the following requirements:

  • Applicants must be from developing countries* who can demonstrate a need for financial assistance.
  • Applicants who are currently living in Japan under a working visa are NOT eligible for the scholarship.
  • Applicants who are already enrolled in other PhD programmes are not eligible. This includes those who have already obtained a PhD degree at an institution other than UNU-IAS.

*Developing countries included in the latest OECD DAC list.

III. Additional Requirements

  • Recipients of the jfUNU Scholarship are required to write a short essay on their learning and experiences at UNU, which is submitted to the donor organisation. Before graduation, each recipient is requested to submit a note of appreciation to the donors with reflections on their future plans.
  • Recipients agree to foster collaboration with jfUNU through participating in jfUNU activities, events, and other opportunities offered to the student body. [Top]