In this paper, a class of preinvex vector interval optimization problems
(VIOP) with gH-subdifferential is considered, and the optimality
conditions and dual results are gained. Firstly, the definition of
subgradient for preinvex interval valued function under
gH-difference is given, and examples are given to verify the
difference between the subgradient in this paper and the subgradient
in[28]. Secondly, by means of gH-subdifferential, the
Karush-Kuhn-Tucker sufficient and necessary conditions for preinvex
(VIOP) are studied. Then, the Mond-Weir dual problem and Wolfe dual
problem of preinvex (VIOP) are established, furthermore, weak duality,
strong duality, and converse duality theorems are obtained by using the
gH-subdifferential. Some examples are given to illustrate the
main results. To some extent, the main results generalize the existing
relevant results.