不同的詞典對這兩個詞的用法有不同的解釋，如《牛津高階英漢雙解詞典》第四版對此的解釋如下：　　

accountable：~ (to sb) (for sth) required or expected to give an explanation for one's actions, etc; responsible （對自己的行為等）應作解說；負責：Who are you accountable to in the organization? 你在這個組織里向誰負責?  He is mentally ill and cannot be held accountable for his actions. 他有精神病, 不能對自己的行為負責。　　

responsible 1. ~ (for sb/sth); ~ (for doing sth) legally or morally obliged, eg to take care of sb/sth or to carry out a duty, and liable to be blamed if one fails （在法律上或道義上）須負責任, 承擔責任：All pilots are responsible for their passengers' safety. 凡是飛機駕駛員均應對乘客的安全負責。I am wholly/partly responsible for the confusion. 我對此混亂情況負有全部[部分]責任。You must make yourself personally responsible for paying these bills. 你應該個人支付這些帳。　　

2.~ to sb/sth having to account for one's actions to an authority or a superior 對自己的行動向主管者或上級承擔責任：be directly/indirectly responsible to the President直接[間接]向總統負責　　

3. ~ (for sth) answerable for one's behaviour 應對自己的行為負責：A drunk man cannot be held/considered fully responsible for his actions. 醉漢不能為其行為負全部責任。　　

但個人認為，兩個在好多情況下可以通用。