The emerging of CAR-T therapy increase the demands of higher standard cleanroom. We will introduce step by step how we build a modular cleanroom recently for CAR-T research and production, including the design parameters, people/material flow, air change rate, pressure control and how the finished cleanroom look like, the test results, and we will also play a video to show what this cleanroom look like. Following this,we will present how modular cleanroom works better than traditional one and share more cases of different types of modular cleanroom.