[en] We report on the first measurement of the g factor of the J^π = 9/2⁺ isomeric state in ⁶⁵Ni. (d,p) reactions on enriched ⁶⁴Ni and ⁶²Ni have been used in order to populate and spin orient the J^π = 9/2⁺ isomeric states in ⁶⁵Ni and ⁶³Ni. The hyperfine field of the Ni target, oriented by an external magnetic field, was used in order to obtain a sufficient number of spin precessions within the relatively short life time of the isomers. The g factor obtained, g(^65mNi) = -0.296(3), is in good agreement with the g factors of other 9/2⁺ states in the region and with shell-model calculations