A platform configuration measurement device including: a configuration register; means for executing extension processing in which a predetermined operation is performed on a content of the configuration register by using a given additional value, a hash value is obtained by applying a predetermined hash function to a value obtained by the predetermined operation, and the hash value is set for a new content of the configuration register; and measurement extension means for obtaining measured values, corresponding to predetermined components constituting a platform, by sequentially making predetermined measurement on the predetermined components, and for allowing the means for executing extension processing to execute the extension processing using the measured values as the additional values, random extension means is provided for allowing the means for executing extension processing to execute the extension processing using a random value as the additional value.