Provided is an electronic mail transmission error determination device, comprising: a feature information generating unit which generates feature information relating to the content of an electronic mail which is to be transmitted; an accumulation unit which accumulates feature information relating to the content of electronic mails which have been transmitted, in association with the destinations of the electronic mails; a destination candidate selection unit which selects, from among the destinations of the electronic mails which have been transmitted, a destination candidate which is similar to the destination of the electronic mail which is to be transmitted; a similarity model generating unit which, for each of the destinations which are accumulated in the accumulation unit, and on the basis of the feature information which is accumulated in the accumulation unit in association with the destination and the feature information which is accumulated in the accumulation unit in association which other destin
