A micro-fluidic system for a perfusion cell culture is disclosed. The system includes: a substrate; a micro-fluid injection channel defined in the substrate to guide fluid in a plane direction of the substrate; at least two micro-fluid branch channels defined in the substrate, wherein the branch channels are branched from the micro-fluid injection channel; micro-fluid outlet channels defined in the substrate, wherein each of the outlet channels extends from a distal end of each branch channel to a top face of the substrate, wherein each outlet channel has each through-hole defined in the top face portion of the substrate; and well plates disposed on the top face of the substrate, wherein each of the well plates fluid-communicates with each outlet channel. The micro-fluidic system refers to a technique that adjusts a flow of liquid or gas of a very small amount (nanoliter or picoliter) in an extremely miniaturized device.