Lotus Software（被IBM收购前名为Lotus Development Corporation）是一家美国软件公司，总部设置在麻萨诸塞州的剑桥。这家公司最著名的软件是Lotus 1-2-3试算表软件，曾是IBM PC平台上被称为杀手级的应用软件。1995年被IBM以35亿美金并购。

在IBM的管治下，Lotus积极开发针对企业市场的群组协作软件平台。当中以Lotus Notes为客户端的Lotus Domino平台为众多企业所采纳，成为该公司目前的旗舰级产品。

Lotus Software (called Lotus Development Corporation before its acquisition by IBM) was an American software company based in Massachusetts. Lotus is most commonly known for the Lotus 1-2-3 spreadsheet application, the first feature-heavy, user-friendly, reliable and WYSIWYG-enabled product to become widely available in the early days of the IBM PC, when there was no graphical user interface. Much later, in conjunction with Ray Ozzie's Iris Associates, Lotus also released a groupware and email system, Lotus Notes. IBM purchased the company in 1995 for US$3.5 billion, primarily to acquire Lotus Notes and to establish a presence in the increasingly important client–server computing segment, which was rapidly making host-based products such as IBM's OfficeVision obsolete.