How to match chinese characters with grep?

To match just lines (filenames) that have Han (Chinese) characters, you can use [\p{Han}] :

ls  /tmp/test | grep -P '[\p{Han}]'

\p{Han} is one Unicode-script category property usable in any PCRE-supporting engine:

\p{Common} \p{Arabic} \p{Armenian} \p{Bengali} \p{Bopomofo}
\p{Braille} \p{Buhid} \p{Canadian_Aboriginal} \p{Cherokee}
\p{Cyrillic} \p{Devanagari} \p{Ethiopic} \p{Georgian} \p{Greek}
\p{Gujarati} \p{Gurmukhi} \p{Han} \p{Hangul} \p{Hanunoo} \p{Hebrew}
\p{Hiragana} \p{Inherited} \p{Kannada} \p{Katakana} \p{Khmer} \p{Lao}
\p{Latin} \p{Limbu} \p{Malayalam} \p{Mongolian} \p{Myanmar} \p{Ogham}
\p{Oriya} \p{Runic} \p{Sinhala} \p{Syriac} \p{Tagalog} \p{Tagbanwa}
\p{TaiLe} \p{Tamil} \p{Telugu} \p{Thaana} \p{Thai} \p{Tibetan}