The International Conference on Parallel Processing (ICPP) is one of the oldest continuously running computer science conferences in parallel computing in the world. It is a premier forum for researchers, scientists, and practitioners in academia, industry, and government to present their latest research findings in all aspects of the field. This year will be the 50th year of ICPP. ICPP2021 will be held at the US Argonne National Laboratory in Chicago, USA and special events will be held to celebrate the 50th anniversary at the conference. ICPP2021 is in cooperation with ACM SIGHPC. We invite everyone to participate in the conference and its celebration.