A control system (1, 1a, 1c) comprising: a control device (100, 100c) configured to execute a control program which, when executed by the control device, causes the control device to control a control target while managing a plurality of pieces of process data referred to or updated in the control program, the control device including a communication processing unit (80, 80c) configured to periodically transmit one or a plurality of predetermined data sets, each data set including values of one or a plurality of predetermined process data in the plurality of pieces of process data; one or a plurality of information processing devices configured to execute one or a plurality of applications using the values of the one or the plurality of process data included in the one or the plurality of data sets transmitted from the control device; an arithmetic unit (300, 300a) configured to determine a transmission setting according to which a data set is generated and transmitted by the communication processing unit of the control device; and a management unit configured to determine a data set for which to enable transmission of one or a plurality of data sets transmittable by the communication processing unit according to one or a plurality of applications that are executed in the one or the plurality of information processing devices, wherein the arithmetic unit includes: an acquisition unit (320, 610) configured to acquire the process data necessary for each of the one or the plurality of applications executed in each of the one or the plurality of information processing devices; and a determination unit (340, 640) configured to determine, based on the process data necessary for each application acquired by the acquisition unit, a number of data sets to be transmitted by the communication processing unit and the process data to be included in each data set according to a predetermined evaluation criterion including a communication load index, wherein the evaluation criterion further includes a management load index that evaluates a load on the management unit by managing determination of the enablement of each of the one or the plurality of data sets, so that process data including values used by applications that are not simultaneously executed is determined to be stored in different data sets. a control device (100, 100c) configured to execute a control program which, when executed by the control device, causes the control device to control a control target while managing a plurality of pieces of process data referred to or updated in the control program, the control device including a communication processing unit (80, 80c) configured to periodically transmit one or a plurality of predetermined data sets, each data set including values of one or a plurality of predetermined process data in the plurality of pieces of process data; one or a plurality of information processing devices configured to execute one or a plurality of applications using the values of the one or the plurality of process data included in the one or the plurality of data sets transmitted from the control device; an arithmetic unit (300, 300a) configured to determine a transmission setting according to which a data set is generated and transmitted by the communication processing unit of the control device; and a management unit configured to determine a data set for which to enable transmission of one or a plurality of data sets transmittable by the communication processing unit according to one or a plurality of applications that are executed in the one or the plurality of information processing devices, wherein the arithmetic unit includes: an acquisition unit (320, 610) configured to acquire the process data necessary for each of the one or the plurality of applications executed in each of the one or the plurality of information processing devices; and a determination unit (340, 640) configured to determine, based on the process data necessary for each application acquired by the acquisition unit, a number of data sets to be transmitted by the communication processing unit and the process data to be included in each data set according to a predetermined evaluation criterion including a communication load index, wherein the evaluation criterion further includes a management load index that evaluates a load on the management unit by managing determination of the enablement of each of the one or the plurality of data sets, so that process data including values used by applications that are not simultaneously executed is determined to be stored in different data sets. an acquisition unit (320, 610) configured to acquire the process data necessary for each of the one or the plurality of applications executed in each of the one or the plurality of information processing devices; and a determination unit (340, 640) configured to determine, based on the process data necessary for each application acquired by the acquisition unit, a number of data sets to be transmitted by the communication processing unit and the process data to be included in each data set according to a predetermined evaluation criterion including a communication load index, wherein the evaluation criterion further includes a management load index that evaluates a load on the management unit by managing determination of the enablement of each of the one or the plurality of data sets, so that process data including values used by applications that are not simultaneously executed is determined to be stored in different data sets.