Autosampler

An autosampler comprising:

• a sample storage having a sample storage space;
• an adjustor having a temperature adjustment space;
• a separating member that has a first opening region and a second opening region and separates the sample storage space and the temperature adjustment space from each other;
• a circulation device that causes gas to circulate between the sample storage space and the temperature adjustment space through the first opening region and the second opening region;
• and
• a heat exchanger that adjusts a temperature of gas flowing in the temperature adjustment space, wherein
• the separating member has first and second unit regions,
• the first and second unit regions have an equal area and an equal shape,
• the second opening region includes a first portion located in the first unit region and a second portion located in the second unit region,
• a shortest distance between the first portion and the first opening region is larger than a shortest distance between the second portion and the first opening region, and
• an aperture ratio of the first portion in the first unit region is larger than an aperture ratio of the second portion in the second unit region.