Plastic pollution is one of the biggest current global threats to the environment given that petroleum-based plastic is recalcitrant and can stay in the environment for decades, even centuries, depending on the specific plastic type. Since less than 10% of all the plastic ever made is recycled and other solutions (such as incineration or landfill storage) are pollutant methods, new environmentally friendly solutions are needed. In this regard, the latest biotechnological discovery on this topic is the capability of insect larvae to use plastic polymers as carbon feedstock. This present review describes the most relevant information on insect larvae capable of degrading plastic, mainly from Galleria mellonella (Fabricius, 1798), Tenebrio molitor (Linnaeus, 1758) and Zophobas atratus (Fabricius, 1776) but also adds new information about other less studied “plastivore” insects such as the termites. The review covers from the very first work describing plastic degradation by larvae in 2014 all the way till the very latest research available (till June 2024) focusing on the identification of a wide variety of plastic-degrading microorganisms isolated from larvae’s gut to date and on the understanding of the potential molecular mechanisms present for the degradation to take place. It also describes the latest discoveries which include the identification of novel enzymes from the waxworm’s saliva.