本文以《稽古錄》的37則臣光曰析論司馬光「國之治亂，盡在人君」的君道思想內涵、意義及特色。司馬光以史資治，主張「人君之道一，其德有三，其才有五。」分人君為五才，肯定創業、中興及守成之君，批評陵夷及亂亡之君，期許人君能修心成德以守成，力學從諫行仁政。人君內以仁、明、武三德修心，三者皆備則國治強，闕一則衰，闕二則危，皆無則亡。人君治國外發而為任官、信賞、必罰的用人之道，用人應采之欲博，辨之欲精，使之欲適，任之欲專及賞罰分明。司馬光概括了歷代君主的德行及歷史興衰，得出具有共性的結論：歷史興衰及政治治亂是因為「道有得失，故政有治亂；德有高下，故功有大小；才有美惡，故世有興衰」，呈現君道決定歷史興衰的思想特色。

This article analyzes the imperial principles of Sima Guang “Jigulu”. Sima Guang advocates the principle of politics lie in the morality of the leaders, so that “Saints obey morality, not law.” The Emperor decides the political Stable or not. Emperors can be divided into five levels: creator, protector, revival, decliner, loser. An ideal Emperor should cultivate his heart with benevolence(仁)、sanity(明)、arbitrariness(武), and the talent of personnel management. The rule of employment are appointment, rewards and punishment. Sima Guang summarized the virtues and historical rise and fall of the monarchs of the past dynasties, and came to a common conclusion: the historical success or failure depends on Emperor’s mind, talent and ability.