后苏联国家（俄语：Постсоветское пространство），也可以称为前苏联国家，是指1991年12月苏联解体之后出现的15个新的独立国家。1990年3月11日，立陶宛首先从苏联宣布独立。之后在1991年8月，同为波罗的海国家的爱沙尼亚和拉脱维亚也宣布独立，并在1991年9月17日加入联合国。波罗的海三国在二战之前本来就是独立国家，1944年被苏联并吞。波罗的海三国独立之后，其他12个国家也相继独立，但这些国家大多加入了独立国家国协。而波罗的海三国从未加入独立国家国协，一开始就以加入欧洲联盟和北大西洋公约组织为目标。

The post-Soviet states, also collectively known as the former Soviet Union (FSU) or former Soviet Republics, are the 15 independent states that emerged from the Union of Soviet Socialist Republics in its dissolution in December 1991, with Russia internationally recognised as the successor state to the Soviet Union. On March 11, 1990, Lithuania was the first to declare its independence, with Estonia and Latvia following suit in August 1991. All three Baltic states claimed continuity from the original states that existed prior to their annexation by the Soviet Union in 1944 and were admitted to the United Nations on 17 September 1991. The remaining 12 republics all subsequently seceded. 12 of the 15 states, excluding the Baltic states, initially formed the CIS and most joined CSTO, while the Baltic states focused on European Union and NATO membership.