Rising demand for the sustainable environment has been enthused interest in the synthesis of a green composite. In the modern era, thermal insulating materials prepared from agro-waste have been concerned globally as they represent a biodegradability and inexpensive alternative to the conventionally derived materials. Nearly 350 million tons of agro-waste is generated through agricultural activity in India which are either land filled or incinerated. The reuse of renewable waste fibers as filler for reinforcement of a polymer composite is a worthwhile option to the environment. This extensive review explores the utilization of agro-waste for synthesis biodegradable thermal resistant composite and methods used for thermal conductivity measurement. Proper utilization of agro-waste is the need of the modern world. In this review, Authors found that agro-waste such as corn cob, corn stalk, rice waste, date palm fiber, durian peel fiber, coconut coir, and straw bales etc. can be blended into the polymer to enhancing its thermal resistant property by lowering their thermal conductivity. This review also investigated an effect of different parameters such as particle size, moisture content, density, and concentration of agro-waste in composite preparation.