A biological-signal measuring apparatus equipped with a trap unit for measuring biological signals of micro-vertebrates, wherein the micro-vertebrates are zebrafish, the biological-signal measuring apparatus comprising: a trap unit having multiple trap channels to which micro-vertebrates are fixable; and wherein the trap channels have a shape formed to fix the head part (h) of the micro-vertebrates put into the trap unit , wherein the trap unit has an injection chamber into which the micro-vertebrates and a fluid are injectable; a transfer channel that is provided to be extended from the injection chamber toward one side and forms a flow channel to transfer the micro-vertebrates and the fluid injected into the injection chamber to the trap channels ; and one or more trap channels which are provided to be extended from the transfer channel in one direction; characterized in that the apparatus further comprises a lifting/lowering unit configured to insert an electrode portion into the micro-vertebrates fixed to the trap unit and measure biological signals, a discharge section , wherein the trap channels each have a plurality of traps formed in a length direction of the trap channels , and wherein the traps have a sectional area which decreases as being positioned downstream such that a trap positioned downstream has a smaller sectional area than a trap positioned relatively upstream. a trap unit having multiple trap channels to which micro-vertebrates are fixable; and wherein the trap channels have a shape formed to fix the head part (h) of the micro-vertebrates put into the trap unit , wherein the trap unit has an injection chamber into which the micro-vertebrates and a fluid are injectable; a transfer channel that is provided to be extended from the injection chamber toward one side and forms a flow channel to transfer the micro-vertebrates and the fluid injected into the injection chamber to the trap channels ; and one or more trap channels which are provided to be extended from the transfer channel in one direction; characterized in that the apparatus further comprises a lifting/lowering unit configured to insert an electrode portion into the micro-vertebrates fixed to the trap unit and measure biological signals, a discharge section , an injection chamber into which the micro-vertebrates and a fluid are injectable; a transfer channel that is provided to be extended from the injection chamber toward one side and forms a flow channel to transfer the micro-vertebrates and the fluid injected into the injection chamber to the trap channels ; and one or more trap channels which are provided to be extended from the transfer channel in one direction; characterized in that the apparatus further comprises a lifting/lowering unit configured to insert an electrode portion into the micro-vertebrates fixed to the trap unit and measure biological signals, a discharge section , wherein the trap channels each have a plurality of traps formed in a length direction of the trap channels , and wherein the traps have a sectional area which decreases as being positioned downstream such that a trap positioned downstream has a smaller sectional area than a trap positioned relatively upstream. <EOS>