A nursing bed posture changing device (10; 10A) that changes a posture of a nursing bed, the nursing bed being changeable of the shape of a floor of the bed, and/or a posture related to an angle of the entire bed, the device (10; 10A) comprising: a care recipient data acquiring module that acquires care recipient data containing at least one of voice data of a care recipient who lies on the nursing bed, and image data obtained by imaging the care recipient; a bed posture information generating module that generates bed posture mode information according to a demand by the care recipient based on the care recipient data; and a posture changing module that changes the posture of the nursing bed based on the bed posture mode information, wherein the bed posture information generating module includes: a care recipient demand feature quantity extracting module that extracts a demand feature quantity by which the care recipient's demand is characterized, from the care recipient data; a memory that stores a plurality of kinds of demands of the care recipient, and the bed posture mode information for identifying the posture of the nursing bed associated with each of the plurality of kinds of demands; and a generating module that reads the bed posture mode information associated with the care recipient's demand corresponding to the demand feature quantity extracted by the care recipient demand feature quantity extracting module, from the memory, wherein the bed posture information generating module further includes a demand identifying module that identifies the care recipient's demand based on a given specific rule from the demand feature quantity, wherein the care recipient data further includes time data indicative of time at which at least one of the voice data and the image data is generated, and wherein the demand identifying module identifies the care recipient's demand based on the demand feature quantity and the time data corresponding thereto. a care recipient data acquiring module that acquires care recipient data containing at least one of voice data of a care recipient who lies on the nursing bed, and image data obtained by imaging the care recipient; a bed posture information generating module that generates bed posture mode information according to a demand by the care recipient based on the care recipient data; and a posture changing module that changes the posture of the nursing bed based on the bed posture mode information, wherein the bed posture information generating module includes: a care recipient demand feature quantity extracting module that extracts a demand feature quantity by which the care recipient's demand is characterized, from the care recipient data; a memory that stores a plurality of kinds of demands of the care recipient, and the bed posture mode information for identifying the posture of the nursing bed associated with each of the plurality of kinds of demands; and a generating module that reads the bed posture mode information associated with the care recipient's demand corresponding to the demand feature quantity extracted by the care recipient demand feature quantity extracting module, from the memory, wherein the bed posture information generating module further includes a demand identifying module that identifies the care recipient's demand based on a given specific rule from the demand feature quantity, wherein the care recipient data further includes time data indicative of time at which at least one of the voice data and the image data is generated, and wherein the demand identifying module identifies the care recipient's demand based on the demand feature quantity and the time data corresponding thereto. a care recipient demand feature quantity extracting module that extracts a demand feature quantity by which the care recipient's demand is characterized, from the care recipient data; a memory that stores a plurality of kinds of demands of the care recipient, and the bed posture mode information for identifying the posture of the nursing bed associated with each of the plurality of kinds of demands; and a generating module that reads the bed posture mode information associated with the care recipient's demand corresponding to the demand feature quantity extracted by the care recipient demand feature quantity extracting module, from the memory, wherein the bed posture information generating module further includes a demand identifying module that identifies the care recipient's demand based on a given specific rule from the demand feature quantity, wherein the care recipient data further includes time data indicative of time at which at least one of the voice data and the image data is generated, and wherein the demand identifying module identifies the care recipient's demand based on the demand feature quantity and the time data corresponding thereto.