A series of polypropylene/multi-walled carbon nanotubes (PP/CNT) nanocomposites were prepared by masterbatch dilution, then followed by microinjection molding under a defined set of processing conditions. A micropart (μ-part) which has a three-step decrease in thickness along the flow direction was fabricated to study the effect of abrupt geometrical changes in mold cavities on the distribution of CNT in PP. To facilitate characterization, the μ-parts were divided into three sections based on thickness. The distribution of CNT within each section of subsequent μ-parts was evaluated by morphological observations and electrical resistivity measurements. In addition, the thermal properties of pure PP and PP/CNT nanocomposites as well as each section of subsequent μ-parts, were assessed by differential scanning calorimetry and thermogravimetric analysis.