战争是罗马历史的主旋律，第二次马其顿战争则是罗马对外战争的重要一环。本文选取第二次马其顿战争爆发的原因作为考察对象，力图从中梳理出罗马发动马其顿战争的真实理由。本文主要分为两部分：一、罗马对马其顿宣战的主观动机；二、第二次马其顿战争爆发的客观原因。罗马元老院决定发动第二次马其顿战争并不是早有预谋的。本文从元老院对埃托利亚同盟使团的拒绝、第二次布匿战争的结果和第二次马其顿战争的结果等方面论证第二次马其顿战争并不是罗马早已设计好的，也不是出于对希腊的热爱。其真正的动机乃是对马其顿的强大感到忧虑，希望通过出兵削弱马其顿在爱琴海地区的势力，维持东部地中海力量的均衡，从而达到其主动防御的目的。当时的客观现实又为罗马成功干预马其顿事务提供了可能。这里既有马其顿的强大对罗马构成的一定威胁，又有东部地中海各国间内部的矛盾。而希腊和小亚诸多国家对罗马的求助，则更是促成罗马介入东方事务挑起马其顿战争的重要原因。罗马对马其顿的宣战正是罗马主观动机和东部客观形势综合作用的结果。而第二次马其顿战争更加速了罗马对东部地中海的征服。

War is the main theme in Roman history, the Second Macedonian War is an important part of Roman external war. The paper discusses the causes for the outbreak of the Second Macedonian War, and trying to coordinate the real reason of Rome launching war to Macedonia.The discussion of the thesis develops in two parts. Firstly, the subjective motives of Rome declaring war to Macedonia; secondly, the objective reasons for the outbreak of the Second Macedonian War. Roman Senate didn’t premeditate to launch the Second Macedonian War. From the fact which the Aetolian League mission was rejected by Roman Senate, the result of the Second Punic War and the result of the Second Macedonian War, this paper comes to the conclusion that Rome didn’t design the Second Macedonian War, nor the altruistic love to Greek was the cause of the war. The real motives were that Rome worried about the powerful Macedonia. Rome wished to weaken the forces of Macedonia in Aegean Sea by war, maintain the balance of power structure in the eastern Mediterranean, and achieve the aim that Rome could defend itself forwardly.The objective situation of the time provided probability of Rome intervening in Macedonia Affairs. It includes the fact that the powerful Macedonia kingdom were threatening to Rome, and the conflicts among many states of the eastern Mediterranean. The appeal of many states in Greece and Asia Minor to Rome is the important reason of Rome intervening in Eastern Affairs and enkindling the Second Macedonian War. Rome finally declared war to Macedonia was the consolidated result of Roman subjective motives and the objective reasons in East. The Second Macedonian War accelerated the Roman conquest of the eastern Mediterranean.