Real and complex Monge-Ampere equations are classical and play a central role in several areas of analysis and geometry. More recently, quaternionic analogues of them were introduced and studied. In this talk we introduce an analogue of the Calabi problem for two octonionic variables.  This is a non-linear elliptic equation of second order formulated for a special class of 16-dimensional manifolds. The problem is solved under extra assumptions on the manifolds (e.g., for 16-dimensional tori). This is a joint work with Peter Gordon.