Wiru or Witu is the language spoken by the Wiru people of Ialibu-Pangia District of the Southern Highlands Province of Papua New Guinea. The language has been described by Harland Kerr, a missionary who lived in the Wiru community for many years. Kerr's work with the community produced a Wiru Bible translation and several unpublished dictionary manuscripts, as well as Kerr's Master's thesis on the structure of Wiru verbs.

There are a considerable number of resemblances with the Engan languages, suggesting Wiru might be a member of that family, but language contact has not been ruled out as the reason. Usher classifies it with the Teberan languages.

Trans–New Guinea–like pronouns are no 1sg (< *na) and ki-wi 2pl, ki-ta 2du (< *ki).

The following basic vocabulary words are from Franklin (1973, 1975), as cited in the Trans-New Guinea database:

Wiru has a general noun-modifying clause construction. In this construction, a noun can be modified by a clause that immediately precedes it. The noun may, but need not, correspond to an argument of the modifying clause. Such constructions can be used to express a wide range of semantic relationships between clause and noun. The follow examples all use the same noun-modifying clause construction:

[No

1SG

ka-k-u]