Applications of Bessel differential equations have attracted the univalent function theorists in recent years. In the present investigation, we establish certain sufficient conditions for Bessel function to be in the class of Janowski starlike and Janowski convex functions. Further, certain sufficient condition for an integral operator defined using Bessel function to be in the class of Janowski starlike and Janowski convex functions are determined. © 2018 by Eudoxus Press, LLC. All rights reserved.