In this work, AlMgB14 was obtained by self-propagating high temperature synthesis (SHS) using the chemical furnace based on titanium and silicon (Ti5Si3) as a source of heat energy. Structure and phase composition of the synthesis products were studied. AlMgB14 formation mechanism was proposed. It was found that the highest yield of AlMgB14 (94 wt %) is achieved with a 2 cm thick chemical furnace. The average size of crystal grains in the obtained AlMgB14-based powder is 1 μm. The duration of AlMgB14 formation is 138 s, which is 30–180 times faster than the duration of high-temperature vacuum sintering. In this case, the SHS method makes it possible to obtain AlMgB14 excluding the energy-consuming stage of heating to the isothermal holding temperature.