Allosteric modulation of catalysis kinetics is prevalent in proteins and has been rationally designed for ribozymes. Here, we present an allosteric DNA molecule that, in its active configuration, catalyzes a noncovalent DNA reaction. The catalytic activity is designed to be modulated by the relative concentrations of two DNA regulator molecules, one an inhibitor and the other an activator. Dynamic control of the catalysis rate is experimentally demonstrated via three cycles of up and down regulation by a factor of over 10. Unlike previous works, both the allosteric receptor and catalytic core are designed, rather than evolved. This allows flexibility in the sequence design and modularity in synthetic network construction.