The results of transport modeling for “breathing” oscillations found recently in the Large Helical Device (LHD) [1] are presented. In the model elaborated the time evolution of the central plasma temperature and density are determined from the energy and particle balance in the plasma core, the boundary temperature is computed from the edge heat balance and the transport of Fe ions over the minor radius is described in a 1-D approximation with a self-consistently computed source due to ionisation of neutrals sputtered at divertor plates. The results of computation substantiate the qualitative explanation proposed earlier [2] and allow to elaborate a physical picture of breathing oscillations consistent with experimental observations. The calculations reproduce well the experimental time evolution of different parameters, their phasing and the variation of the amplitude and period of oscillations with plasma characteristics.