An adjustable kettlebell or exercise device includes a handle device formed on a receptacle, and one or more weight members selectively engageable into the receptacle, and a control device includes a shaft engaged through the receptacle and engageable through the weight members for selectively anchoring either of the weight members to the receptacle with the shaft. The weight members each include a bore for engaging with the shaft, and an opening communicating with the bore of the weight members, and the shaft includes one or more pins engageable through the openings of the weight members for selectively engaging with the weight members.