Karen Yongjie Xi is an associate in the Banking & Finance practice in Mayer Brown's Tokyo office. Her practice focuses on M&A, project finance and other general banking and corporate matters. 

Prior to joining the firm, Karen worked at the New York and Shanghai offices of international banks. Before that, she worked for a projects group in another international law firm’s Tokyo office. While working there, she completed a part time secondment to one of Japan's largest power utilities.

Spoken Languages

  • Mandarin
  • Japanese
  • English


  • Advised a Japanese utility, a trading company, and a Japanese bank on a joint investment into a greenfield thermal power plant in China.
  • Advised a Japanese trading house on its acquisition of 20% stake of one of the largest food conglomerates in mainland China and Taiwan.
  • Acted for two Japanese utilities in their acquisition of interest in a power company holding a portfolio of multiple power plants in China.
  • Advised a Japanese lender on a $7 billion financing of an LNG liquefaction facility project in Louisiana, USA.
  • Advised a Japanese lender on refinancing of a power plant project in Texas, USA.
  • Worked for a Japanese lender on the first NEXI agriculture financing project in Brazil.
  • Worked for a Japanese lender in connection with the financing of a copper mining project in Chile.
  • Acted for a Japanese lender on its financing of an LNG terminal project in Texas, USA.
  • Represented a NASDAQ-listed company on its acquisition of two Japanese companies.  
  • Acted for a client in restructuring and selling-off of subsidiaries in Japan.
  • Acted for multiple overseas clients in setting up companies in Japan.
  • Worked for a bank on multiple ISDA relevant documents. 


University of Pennsylvania Law School, LLM

Keio University, LLM

Fudan University, BA


  • New York
  • PRC