I heard it was easy, but it took a long time, so Make a note of the referenced page.
By the way, my environment is: ・ Gravo: NVIDIA TITAN Z ・ OS: CentOS 6.7 ・ Python: 2.7.8 ・ Chainer: 1.7.0 ・ Cuda: 7.5 It is like this.
・ Chainer's official website (First from here.) http://docs.chainer.org/en/stable/install.html
・ Installation of CUDA 7.5 (Note that the runlevel change method is different between CentOS 6 and 7. But I'm not sure if I needed to change the runlevel this time. ) https://www.softek.co.jp/SPG/Pgi/TIPS/public/accel/cuda75_install.html
・ CuDNN settings (I had to manually copy the files to include and lib.) http://takatakamanbou.hatenablog.com/entry/2015/08/25/120326
・ TIPS on CentOS6 (If the version of gcc is old, it seems that it can not be calculated by GPU.) http://qiita.com/naoh16/items/2693645ab2733faf1aa5 → It didn't work as it was, so I tried the wget procedure and it worked. http://www.task-notes.com/entry/20151114/1447492231
・ TIPS collection of chainer1.5 (It is necessary to set various environment variables.) http://qiita.com/unnonouno/items/c491b6df59352159cbf0