共同对象文件格式（英语：Common Object File Format，缩写为COFF），又称通用目标文档格式，一种用于运行档、目标代码、共享库（shared library）的文件格式，使用于类UNIX系统上。它最早使用于UNIX System V上，用来取代先前的a.out格式，后来又发展出XCOFF与ECOFF。

在多数类UNIX系统上，这个格式已被ELF格式所取代。某些类Unix系统，微软公司的Windows系统，可扩展固件接口以及某些嵌入式系统中仍在使用COFF文档格式或它的变种。

The Common Object File Format (COFF) is a specification of a format for executable, object code, and shared library computer files used on Unix systems. It was introduced in Unix System V, replaced the previously used a.out format, and formed the basis for extended specifications such as XCOFF and ECOFF, before being largely replaced by ELF, introduced with SVR4. COFF and its variants continue to be used on some Unix-like systems, on Microsoft Windows, in EFI environments and in some embedded development systems.