Ratanak earns a Master's degree of Master Business Administration from Norton University of Cambodia in 2011. Ratanak has spent almost 16 years of working experiences in Financial Management, Grant Management, Taxation, Administration and Supply Chain in Emergency Response with International Organizations including Oxfam Australia, Habit for Humanity, ActionAid, BBC Media Action and Caritas Cambodia and I also have been working with many donors such as BMZ, UN Agency, EU, SIDA, USAID, DFAT, Catholic Church and private donors.

Ratanak joins Oxfam in 2021 as a Program Finance Officer for Natural Resource Governance (NRG) and Voice Program. He is responsible for developing a financial management framework for the implementation of the grants and partnership agreements incorporating all local partners and provide the orientation and coaching partners. He also produces the financial reports to donors, financial audit ensuring proper accountability and transparency and efficiency and effectiveness of using funds.

"I'm inspired by the work Oxfam does. I'm here being part of Oxfam team to solve those issues to promote justices and help vulnerable people," said Ratanak.