Abstract: Provided are a reply recommendation apparatus using collected data, and a system and method for automatic text construction. The reply recommendation apparatus includes a data collecting unit collecting dialog pair data including parent text data corresponding to a query and child text data, a data pre-processing unit pre-processing the collected data pair data, a vectorizing unit matching the pre-processed data to particular points on the coordinate system having predefined axes, a clustering unit performing clustering using information on the matched particular points and merging all or some of texts included in one of clusters using a preset merging method, a ranking unit scoring the degree of appropriateness as a reply to the received message for each of the clusters using a first preset scoring method, and a recommended reply providing unit providing recommended replies sequentially represented by high score assigned when the ranking unit scores the degree of appropriateness.