Carbon nanotubes/ iron compound powder was prepared by high energy ball milling after purified and activated the CNTs. Then, the compound powder and paraffin wax based-binders were mixed to prepare feedstock and the rheological behavior was evaluated by SEM, rheometer and infrared spectrum analysis. By changing the CNTs content and powder loading, the viscosity, shear rate sensitive factor and viscos-activation energy were calculated. 0.2wt% of CNTs, the feedstock can disperse in the binders uniformly without the flowability affecting. Meanwhile, adding proper ratio of CNTs can increase the powder loading of MIM feedstock about 10%, which can optimize the following process conditions and the properties of MIM product.