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• A hybrid magnetic field produced by microwires and Halbach magnets is proposed to enhance the mixing between ferrofluid and water. • We numerically and experimentally analyze the effects of the arrangement and the number of microwires on the mixing efficiency. • By adjusting the direction and the magnetite of uniform magnetic field, we receive optimal mixing efficiency 99.06%. With the development in biomedical and biotechnological areas, novel and efficient microfluidic devices integrated with sufficient and rapid mixing function have been attracting enormous scientific attention as versatile and robust platform for low cost and non-contact biological analysis and diagnose. Here, we design and fabricate a magnetic micromixer integrated with special designed microwires, a Y-shaped microchannel and uniform magnetic field for realizing rapid mixing between ferrofluid and deionized water. A comprehensive analysis on the dynamic behavior of ferrofluid is performed by using 3D Eulerian-Eulerian model. Good consistency between experiment and numerical results demonstrates that the enhanced mixing in the presence of longitudinally arranged microwires is due to the introduction of eddies, whose impacts are strengthened with the increase of the number of microwires (n w). However, increasing n w requires a long microchannel and long time to complete mixing. In order to further improve the mixing performance of our micromixer, a horizontally arranged microwire combined with a particular uniform magnetic field is proposed to provide enough magnetic force for enhancing the mixing of ferrofluid and deionized water, receiving optimal mixing efficiency 99.06%. The flexible tunability of external uniform magnetic field enables desired performance of our designed system. [ABSTRACT FROM AUTHOR]