西亞兩河流域古代王朝。公元前16世紀由加喜特人，剋喜特人，喀西特人 （Kassites)建立。又稱加喜特巴比倫、巴比倫第三王朝。
加喜特人原居於札格羅斯山脈中部。公元前16世紀初占據巴比倫，建加喜特王朝。此時約當阿古姆二世時期。布爾納布裏亞什二世至卡什提裏亞什四世期間（約前14世紀中～前13世紀後半），為其繁榮時期，與埃及新王國、赫梯帝國、亞述同為並立的大國。公元前13世紀後半期，亞述人和埃蘭人入侵。約公元前1157年，加喜特王恩利爾納丁·阿基被埃蘭人拐走，加喜特王朝滅亡。
加喜特人在入主兩河流域後，將侵占的土地分配給本族的朝臣、貴族和官吏，形成大地産私有主。其政治體製基本上是貴族政治，後期地方貴族勢力日趨強大，王權削弱。加喜特人恢復了兩河流域的秩序、和平和統一，特別是在其統治的中後期，社會經濟有所發展，巴比倫、尼普爾、西巴爾等城市經濟相當繁榮。人們在兩河流域推廣用於牽引的馬和戰車，並在建築物上以磚刻浮雕代替石雕。這一風格為以後的新巴比倫王國和阿契美尼德王朝所繼承。
加喜特人全面接受兩河流域固有的文化、宗教和阿卡德語言文字，迅速塞姆化。其國王重建和修飾尼普爾、拉爾沙、烏爾、烏魯剋等地的神廟。這一時期的重要遺物“界碑”，實際是國王所授地産的憑證。史稱此時為界碑時代，即得名於此。界碑的右面或上部刻神像或神的象徵，如以圓盤象徵太陽神沙馬什，以月牙象徵月神欣，以鋤頭象徵馬爾杜剋等；左面或下部的銘文多為王授土地情況。
The Kassite dynasty was founded by Kandis or Gandash of Mari. The Kassites renamed Babylon "Kar-Duniash", and their rule lasted for 576 years. This foreign dominion offers a striking analogy to the roughly contemporary rule of the Hyksos in ancient Egypt. Babylonia having lost its empire over western Asia, the high-priests of Ashur made themselves kings of Assyria. Most divine attributes ascribed to the Semitic kings of Babylonia disappeared at this time; the title of God was never given to a Kassite sovereign. However, Babylon continued to be the capital of the kingdom and the 'holy' city of western Asia, where the priests were all-powerful, and the only place where the right to inheritance of the old Babylonian empire could be conferred.
Despite the loss of territory, and evident reduction in literacy and culture, the Kassite dynasty was the longest-lived dynasty of Babylon, lasting until 1155 BC (short), when Babylon was conquered by Shutruk-Nahhunte of Elam, and re-conquered a few years later by Nebuchadrezzar I, part of the larger Bronze Age collapse.