  We propose that Hawking radiation-like phenomena may be observed in systems
that show butterfly effects. Suppose that a classical dynamical system has a
Lyapunov exponent $\lambda_L$, and is deterministic and non-thermal ($T=0$). We
argue that, if we quantize this system, the quantum fluctuations may imitate
thermal fluctuations with temperature $T \sim \hbar \lambda_L/2 \pi $ in a
semi-classical regime, and it may cause analogous Hawking radiation. We also
discuss that our proposal may provide an intuitive explanation of the existence
of the bound of chaos proposed by Maldacena, Shenker and Stanford.
