Recent activities in Japan to deploy a data grid for high energy physics will be reported. Japanese collaboration of LHC-ATLAS experiment is now preparing a Tier-2 analysis center at Tokyo. Several institutes/universities have grid facilities and they are connected to the Tokyo Tier-2 center. Collaborators of Phenix of RHIC at BNL and CDF of Tevatron at FNAL are also using grid tools for data transmission. KEK-CRC is also hosting the Belle experiment VO and is running a site for it as a part of LCG. A general purpose virtual organization for Japanese high energy physics society is to be launched. Key words: Data Grid, High Energy Physics, Distributed Data Analysis, Data Transmission, TCP Protocol