The present paper deals with the mixed mode fracture analysis of a weakened orthotropic half-plane with multiple cracks propagation. The orthotropic half-plane contains Volterra type glide and climb edge dislocations. It is assumed that the medium is under in-plane loading conditions. The distributed dislocation technique is used to obtain integral equations for the dynamic problem of multiple smooth cracks which are located in an orthotropic half-plane. At first, with the help of Fourier transform the dislocation problem is solved and the stress fields are obtained. The integral equations are of Cauchy type singularity and are solved numerically to obtain the dislocation densities on the surface of several cracks to determine the dynamic stress intensity factors on the crack tips. Several numerical examples are solved to evaluate mode I and mode II dynamic stress intensity factors to show the effects of the orthotropy parameters, crack lengths, and crack speed on the dynamic stress intensity factors.