A unique demonstration with ball-rolling mechanisms has been developed to illustrate the basic principles of mass analyzers as components of mass spectrometers. Three ball-rolling mechanisms mimicking the currently used mass analyzers (i.e., a quadrupole mass filter, a magnetic sector, and a time-of- flight) have been constructed. Each mechanism was designed to separate balls with three different weights (representing three ionized analytes with different weights) in an attempt to imitate the separation process employed by real mass analyzers. This demonstration helped students understand the basic principles of mass analyzers.