A navigation apparatus which is capable of voice guidance by outputting a voice message, comprising: a detection part for detecting a location and a speed of the navigation apparatus; a voice message weight storage part for storing voice message weight association information that associates a weight with each of multiple voice messages; a rule storage part for storing priority rule information denoting a rule for deciding a priority for each of the multiple voice messages; a priority decision part for deciding a priority for each of the multiple voice messages based on the priority rule information; and a voice output part for outputting the multiple voice messages in a sequence conforming to the decided priority, wherein a rule denoted by the priority rule information is a rule for deciding a priority for each voice message based on the detected location and speed of the navigation apparatus, and the weight of each of the voice messages denoted by the voice message weight association information, characterized by a storage part for storing reference driving performance information, which is driving performance characteristics information constituting a reference; a characteristics acquisition part for acquiring driving performance characteristics of a driver, who drives a vehicle comprising the navigation apparatus; and an evaluation score calculation part for calculating an evaluation score of the driver based on the reference driving performance information and the driving performance characteristics of the driver, wherein the rule denoted by the priority rule information is a rule for deciding a priority for each of the voice messages based also on the evaluation score of the driver. a detection part for detecting a location and a speed of the navigation apparatus; a voice message weight storage part for storing voice message weight association information that associates a weight with each of multiple voice messages; a rule storage part for storing priority rule information denoting a rule for deciding a priority for each of the multiple voice messages; a priority decision part for deciding a priority for each of the multiple voice messages based on the priority rule information; and a voice output part for outputting the multiple voice messages in a sequence conforming to the decided priority, wherein a rule denoted by the priority rule information is a rule for deciding a priority for each voice message based on the detected location and speed of the navigation apparatus, and the weight of each of the voice messages denoted by the voice message weight association information, characterized by a storage part for storing reference driving performance information, which is driving performance characteristics information constituting a reference; a characteristics acquisition part for acquiring driving performance characteristics of a driver, who drives a vehicle comprising the navigation apparatus; and an evaluation score calculation part for calculating an evaluation score of the driver based on the reference driving performance information and the driving performance characteristics of the driver, wherein the rule denoted by the priority rule information is a rule for deciding a priority for each of the voice messages based also on the evaluation score of the driver.