In recent years

inertial microfluidics has become an important tool for manipulating particles and cells

and has important applications in medical diagnosis

material synthesis and biochemical reactions. The inertial effect of microfluidics enables precise manipulation of particles at high throughputs. Inertial lift forces the particles to migrate laterally within the microchannels and regulates particle motion by changing microchannel dimensions

inlet flow velocity

and other conditions to achieve focusing of particles of different sizes. Dean’s drag and centrifugal forces in non-straight microchannels also play an important role in particle migration

and the addition of these two forces helps to improve focusing efficiency. The latest research progress of various types of inertial migration of particles in straight passage and curved passage are reviewed. The principle and application of particle migration in various types of passage are expounded in detail. The development status and problem to be solved in development of inertial microfluidics in the future are discussed.