Yes, frogs are vertebrates and have a spine, or backbone. The skeleton of a frog is very similar to other vertebrates, such as humans, although some parts have changed to better fit the frog's lifestyle.
Some vertebrae of the frog's spine have fused into a single bone called a urostyle, which is one key difference in the spine of a frog and that of other mammals. Frogs' spines also do not have a neck portion. Because of this change, frogs are unable to move their heads up, down or side-to-side. The pelvis has the ability to move along the spine, and the spine no longer connects to a rib cage, since frogs lack ribs.