Our ultimate goal is to design, fabricate, and test a new platform for malaria diagnosis using an array of magnets located parallel to a straight microchannel. The principle of the diagnosis is to attract malaria-infected blood cells using a nonuniform magnetic field induced by the array of magnets, while healthy blood cells are not affected and move along the flow direction. To achieve the goal, a mathematical model for predicting blood-cell motion was developed and validated using magnetic particles. In the experiments, trajectories of magnetic particles were captured using a photographic technique as the particles moved inside the system. The study has revealed that the trajectories of the magnetic particles obtained from both computational and experimental results were in a good agreement, and the mean deviation between them was around 18% for both 5 and 10 µm magnetic particles. In addition, the simulation results for malaria-infected mouse blood cells suggested that at the distance of 400 µm from the magnet array, the infected blood cells could move laterally toward the magnet array at distances around 35.2, 26.9, 21.8, and 18.3 µm within a 3 cm downstream distance at flow rates of 0.18, 0.23, 0.28, and 0.33 µL/min, respectively.