The characterization and commissioning of composite structures for impact resistance requires extensive analytical, computational and experimental studies. It is usually necessary that scaled model tests are carried out that represent real structure behavior as much as possible. Reliable methods are thus required that provide accurate scaling rules for dynamic similarity between models and prototypes. This paper presents a general similitude method for scaling the low-velocity impact response of different composite structures. It is demonstrated that impact cases or situations in different structures having the same set of three non-dimensional parameters will be dynamically similar, and have the same normalized impact response despite being different with respect to their type, boundary conditions, materials and size. In cases of simple structures, such as rods, beams and plates with standard boundary conditions, the parameters can be obtained analytically. In cases of complex structures and boundary conditions, either finite element simulations or simple physical experiments can be carried out to measure the necessary parameters. It is expected that the proposed similitude rules will help researchers to optimize their resources for parametric and experimental studies. © 2009 Elsevier Ltd. All rights reserved.