Provided is a micro-fluid chip that enables reducing contamination between branch channels, has a relatively simple channel structure and facilitates miniaturization. A micro-fluid chip (1) having a channel structure (3) through which a fluid is delivered, wherein the channel structure (3) includes: a main channel (4) having an inflow port (5) and an outflow port (6); a plurality of branch channels (11) to (13) connected to the main channel (4), each branch channel having an inflow end on a side connected to the main channel (4) and an outflow end that is an end portion on an opposite side to the inflow end; and a sub-branch channel (14) connected to the main channel (4) between at least one pair of adjacent branch channels (11) and (12) among the plurality of branch channels (11) to (13), the sub-branch channel (14) having an inflow end on a side connected to the main channel (4).