It is noted that the free harmonic vibrations of a classical pendulum are due to the mutual conversion of the kinetic energy of the load intothe potential energy of the spring. Oscillators with a different nature of energy exchange have been developed, for example, by converting the kinetic energy of a load into the energy of a magnetic field of a solenoid or the energy of an electric field of a capacitor. All these oscillatory systems and the like were a prerequisite for the creation of a biinert oscillator,in which the acceleration of one load occurs due to the braking of another, i. e. only kinetic energies are exchanged. The aim of the work is mathematical modeling of a multi-inert oscillatory mechanism. The main research methods in the framework of this work are methods of mathematical modeling and analysis. The methods used make it possible to obtain a reliable description of the studied objects. Inthe proposed multi-inert oscillator, inert bodies of mass m each carry out harmonic oscillations due to the mutual exchange of kinetic energy. The potential energy of the springs is not requiredfor this. Body vibrationsare free. A feature of a multi-inert oscillator is that the frequency of itsfree oscillations is not fixed and is determined mainly by the initial conditions. This feature can be very useful for technical applications, for example, for self-neutralization of mechanical reactive (inertial) power. n-gon, formed by inert bodies, carries out complex motion – orbital rotation around the center of coordinates and spin rotation around its axis passing through the center of the n-gon. Moreover, each load performs linear harmonic oscillations along its guide. With the arrangement of the guiding weights not in the form of a star, but in parallel to each other, the angles between the corresponding cranks must be 360/n degrees.