RNA extraction is a critical first step in many molecular biology applications, including gene expression analysis, RT-PCR, and RNA sequencing. The Trizol reagent (also known as TRI reagent) is a widely used reagent for the extraction of total RNA from various biological samples, including tissues, cells, and fluids. This protocol outlines the use of Trizol for RNA extraction from cell cultures grown in 6-well plates. Trizol provides a highly effective and efficient method for isolating RNA, as it simultaneously disrupts cells, denatures proteins, and separates RNA from DNA and lipids. The 6-well plate method is designed to process multiple samples in parallel, making it suitable for high-throughput experiments. This protocol is ideal for researchers requiring high-quality RNA for downstream applications such as quantitative PCR (qPCR), Northern blotting, or RNA sequencing. Proper handling of the samples during the extraction process ensures RNA purity and integrity, critical factors for obtaining reliable and reproducible results.