AT&T公司(si)(si)（英語(yu)：AT&T Inc.，原為American Telephone & Telegraph的(de)縮寫，也是(shi)(shi)中文譯(yi)名美國(guo)電話(hua)電報公司(si)(si)由來，但近年(nian)來已不用全名），是(shi)(shi)一家美國(guo)電信公司(si)(si)，創建(jian)于1877年(nian)。 AT&T在近120年(nian)中，曾經過多(duo)次分拆和重組。 AT&T也是(shi)(shi)是(shi)(shi)美國(guo)NBA聯盟(meng)圣安(an)東尼奧(ao)馬刺的(de)球館英語(yu)名AT&T Center。

美(mei)國(guo)(guo)(guo)電(dian)(dian)(dian)話(hua)電(dian)(dian)(dian)報公(gong)(gong)(gong)司(si)有(you)8個(ge)主(zhu)要部(bu)門 ：貝爾(er)(er)實驗室、商業(ye)市(shi)場集團、數據系(xi)統(tong)(tong)公(gong)(gong)(gong)司(si) 、通用(yong)市(shi)場集團 、網絡(luo)運營集團、網絡(luo)系(xi)統(tong)(tong)集團、技術(shu)系(xi)統(tong)(tong)集團、公(gong)(gong)(gong)司(si)國(guo)(guo)(guo)際(ji)集團。主(zhu)要業(ye)務(wu)是：為(wei)國(guo)(guo)(guo)內國(guo)(guo)(guo)際(ji)提(ti)供(gong)電(dian)(dian)(dian)話(hua)服務(wu)。利用(yong)海底電(dian)(dian)(dian)纜(lan)、海底光纜(lan)、通信(xin)衛星，可聯系(xi)250個(ge)國(guo)(guo)(guo)家和(he)(he)地區，147個(ge)國(guo)(guo)(guo)家和(he)(he)地區可直(zhi)接撥號。提(ti)供(gong)商業(ye)機器、數據類(lei)(lei)產(chan)品(pin)和(he)(he)消費類(lei)(lei)產(chan)品(pin)。提(ti)供(gong)電(dian)(dian)(dian)信(xin)網絡(luo)系(xi)統(tong)(tong)。各(ge)種(zhong)服務(wu)及(ji)租賃業(ye)務(wu)。它還為(wei)政府(fu)提(ti)供(gong)產(chan)品(pin)和(he)(he)服務(wu)。該公(gong)(gong)(gong)司(si)非(fei)常重(zhong)視(shi)科研和(he)(he)開發(fa)新(xin)產(chan)品(pin)。美(mei)國(guo)(guo)(guo)電(dian)(dian)(dian)話(hua)電(dian)(dian)(dian)報公(gong)(gong)(gong)司(si)在(zai)泰國(guo)(guo)(guo)、德國(guo)(guo)(guo)、新(xin)加坡(po)等地設(she)(she)有(you)工廠(chang)。在(zai)意(yi)大利、韓國(guo)(guo)(guo)、日本等國(guo)(guo)(guo)設(she)(she)有(you)子公(gong)(gong)(gong)司(si)或者合資公(gong)(gong)(gong)司(si)。1995年(nian)9月，該公(gong)(gong)(gong)司(si)解(jie)體(ti)為(wei)三個(ge)獨(du)立的(de)(de)公(gong)(gong)(gong)司(si)：通訊服務(wu)公(gong)(gong)(gong)司(si)、通訊設(she)(she)備公(gong)(gong)(gong)司(si)、電(dian)(dian)(dian)腦信(xin)息服務(wu)公(gong)(gong)(gong)司(si)，并且退出(chu)個(ge)人電(dian)(dian)(dian)腦領域。AT&T的(de)(de)瓦解(jie)過程(cheng)開始于1984年(nian)。在(zai)美(mei)國(guo)(guo)(guo)政府(fu)反壟斷政策的(de)(de)強制干預(yu)下，公(gong)(gong)(gong)司(si)的(de)(de)本地電(dian)(dian)(dian)話(hua)業(ye)務(wu)被分(fen)裂出(chu)去，重(zhong)新(xin)組建了7個(ge)子公(gong)(gong)(gong)司(si)，分(fen)別是：貝爾(er)(er)太平(ping)洋(yang)公(gong)(gong)(gong)司(si)、Ameritech公(gong)(gong)(gong)司(si)、貝爾(er)(er)西(xi)南公(gong)(gong)(gong)司(si)、貝爾(er)(er)西(xi)部(bu)美(mei)國(guo)(guo)(guo)公(gong)(gong)(gong)司(si)、貝爾(er)(er)大西(xi)洋(yang)公(gong)(gong)(gong)司(si)、貝爾(er)(er)南方(fang)公(gong)(gong)(gong)司(si)和(he)(he)Nynex公(gong)(gong)(gong)司(si)。