A preparative chromatograph system comprising: a sample injector that injects a sample into a separation flow path through which a mobile phase flows; a separation column that is provided on the separation flow path and is to separate a sample injected into the separation flow path into components; a detector that is provided at a position farther downstream than the separation column on the separation flow path and is to detect sample components obtained by separation in the separation column; a collector (18, 18') having a plurality of collection containers for collecting part of an eluate eluted from the separation column and a switch mechanism configured to be capable of selectively connecting a downstream end of the separation flow path to any one of the collection containers; a collection setter configured to be capable of setting a portion, to be collected in each of the collection containers, of an eluate eluted from the separation column using a pre-acquired chromatogram of a sample, and the collection setter configured to set a portion, including a sample component, of an eluate eluted from the separation column, and a portion, between two sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column, as the portion to be collected; and a controller configured to control an operation of the switch mechanism of the collector (18, 18') and collect the portion, which is to be collected and is set by the connection setter, in the predetermined collection container, wherein the switch mechanism includes a switch valve for selectively switching the collection container into which an eluate eluted from the separation column is introduced, the switch valve includes a plurality of ports, and the plurality of ports include a port to which a collection container that collects a portion, including a sample component, of an eluate eluted from the separation column is connected, and a port to which a collection container that collects only a portion, between two sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column, is connected, and wherein the port to which a collection container for collecting a portion, between first and second sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column is connected is provided between the port to which a collection container for collecting the first sample component is connected, and the port to which a collection container for collecting the second sample component is connected, to be continuous to these ports. a sample injector that injects a sample into a separation flow path through which a mobile phase flows; a separation column that is provided on the separation flow path and is to separate a sample injected into the separation flow path into components; a detector that is provided at a position farther downstream than the separation column on the separation flow path and is to detect sample components obtained by separation in the separation column; a collector (18, 18') having a plurality of collection containers for collecting part of an eluate eluted from the separation column and a switch mechanism configured to be capable of selectively connecting a downstream end of the separation flow path to any one of the collection containers; a collection setter configured to be capable of setting a portion, to be collected in each of the collection containers, of an eluate eluted from the separation column using a pre-acquired chromatogram of a sample, and the collection setter configured to set a portion, including a sample component, of an eluate eluted from the separation column, and a portion, between two sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column, as the portion to be collected; and a controller configured to control an operation of the switch mechanism of the collector (18, 18') and collect the portion, which is to be collected and is set by the connection setter, in the predetermined collection container, wherein the switch mechanism includes a switch valve for selectively switching the collection container into which an eluate eluted from the separation column is introduced, the switch valve includes a plurality of ports, and the plurality of ports include a port to which a collection container that collects a portion, including a sample component, of an eluate eluted from the separation column is connected, and a port to which a collection container that collects only a portion, between two sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column, is connected, and wherein the port to which a collection container for collecting a portion, between first and second sample components that are adjacent to each other on the chromatogram, of an eluate eluted from the separation column is connected is provided between the port to which a collection container for collecting the first sample component is connected, and the port to which a collection container for collecting the second sample component is connected, to be continuous to these ports.