A high-density micro-chamber array, comprising: a first micro-chamber member comprising: a flat first substrate; a plurality of first micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic first material on a surface of the first substrate to be arrayed regularly at a high density; and a first lipid membrane that is formed at openings of the plurality of first micro-chambers filled with a first aqueous test solution to liquid-seal the first aqueous test solution; and a second micro-chamber member comprising: a flat second substrate; a plurality of second micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic second material on a surface of the second substrate to be arrayed regularly at a high density; and a second lipid membrane that is formed at openings of the plurality of second micro-chambers filled with a second aqueous test solution to liquid-seal the second aqueous test solution, wherein the first lipid membrane and the second lipid membrane form a lipid bilayer membrane by joining each surface of the first lipid membrane and the second lipid membrane, each of the plurality of second micro-chambers of the second micro-chamber member is formed to be aligned with at least one of the plurality of first micro-chambers when a surface of the first micro-chamber member having the plurality of first micro-chambers thereon and a surface of the second micro-chamber member having the plurality of second micro-chambers thereon are joined as joint surfaces, the first micro-chamber member and the second micro-chamber member are joined with each other such that the surface of the first micro-chamber member having the plurality of first micro-chambers formed thereon is in contact with the surface of the second micro-chamber member having the plurality of second micro-chambers formed thereon. a first micro-chamber member comprising: a flat first substrate; a plurality of first micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic first material on a surface of the first substrate to be arrayed regularly at a high density; and a first lipid membrane that is formed at openings of the plurality of first micro-chambers filled with a first aqueous test solution to liquid-seal the first aqueous test solution; and a flat first substrate; a plurality of first micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic first material on a surface of the first substrate to be arrayed regularly at a high density; and a first lipid membrane that is formed at openings of the plurality of first micro-chambers filled with a first aqueous test solution to liquid-seal the first aqueous test solution; and a second micro-chamber member comprising: a flat second substrate; a plurality of second micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic second material on a surface of the second substrate to be arrayed regularly at a high density; and a second lipid membrane that is formed at openings of the plurality of second micro-chambers filled with a second aqueous test solution to liquid-seal the second aqueous test solution, wherein a flat second substrate; a plurality of second micro-chambers, each having a capacity of not greater than 4000×10 -18 m 3, that are formed from a hydrophobic second material on a surface of the second substrate to be arrayed regularly at a high density; and a second lipid membrane that is formed at openings of the plurality of second micro-chambers filled with a second aqueous test solution to liquid-seal the second aqueous test solution, wherein the first lipid membrane and the second lipid membrane form a lipid bilayer membrane by joining each surface of the first lipid membrane and the second lipid membrane, each of the plurality of second micro-chambers of the second micro-chamber member is formed to be aligned with at least one of the plurality of first micro-chambers when a surface of the first micro-chamber member having the plurality of first micro-chambers thereon and a surface of the second micro-chamber member having the plurality of second micro-chambers thereon are joined as joint surfaces, the first micro-chamber member and the second micro-chamber member are joined with each other such that the surface of the first micro-chamber member having the plurality of first micro-chambers formed thereon is in contact with the surface of the second micro-chamber member having the plurality of second micro-chambers formed thereon.