We study chaos and turbulence on classical closed strings in nonintegrable string theory. The string motion is considered in the five-dimensional anti-de Sitter (AdS) soliton spacetime taken as the target space. We first revisit classical chaos using a cohomogeneity-1 string ansatz. We then turn to turbulent behaviors of the classical strings when the spatial dependence of the string world sheet is included. Sensitivity to initial conditions in chaotic systems suggests that the string under chaos tends to stretch in the AdS soliton spacetime in a Lyapunov time scale. In this process, the orbital angular momentum transfers to internal spin due to the turbulence on the string. It follows that the string stays around the tip of the AdS soliton with a jumbled profile. We evaluate the spectra of conserved quantities and discuss their universal power-law scalings in the turbulent behaviors.