The strain distributions and of reflection high-energy electron diffraction (RHEED) patterns of uncapped pyramidal shape InAs Stranski-Krastanov quantum dots fabricated on GaAs(0 0 1) substrate are investigated theoretically. Three-dimensional strain anisotropy is computed with an atomistic elasticity approach, using inter-atomic Keating potentials and the strain energy is minimized using the conjugate gradient numerical method. RHEED images are predicted in the framework of the kinematical theory, by taking into account the refraction of the electron beam at the quantum dot/vacuum interface. Clear correlation between RHEED image features and quantum dot structural properties is established showing that even rather small strain anisotropies imply noticeable changes in RHEED images stressing the potential of RHEED in detecting and deciphering real-time strain distributions in quantum dots. (c) 2007 Elsevier B.V. All rights reserved.