ISO/IEC 8859-5:1999, Information technology — 8-bit single-byte coded graphic character sets — Part 5: Latin/Cyrillic alphabet, is part of the ISO/IEC 8859 series of ASCII-based standard character encodings, first edition published in 1988. It is informally referred to as Latin/Cyrillic. It was designed to cover languages using a Cyrillic alphabet such as Bulgarian, Belarusian, Russian, Serbian and Macedonian but was never widely used. It would also have been usable for Ukrainian in the Soviet Union from 1933 to 1990, but it is missing the Ukrainian letter ge, ґ, which is required in Ukrainian orthography before and since, and during that period outside Soviet Ukraine. As a result, IBM created Code page 1124.

ISO-8859-5 is the IANA preferred charset name for this standard when supplemented with the C0 and C1 control codes from ISO/IEC 6429.

The 8-bit encodings KOI8-R and KOI8-U, CP866, and also Windows-1251 are far more commonly used. In contrast to Windows-1252 and ISO 8859-1, Windows-1251 is not closely related to ISO 8859-5. The Windows code page for ISO-8859-5 is code page 28595 a.k.a. Windows-28595.

The Unicode main Cyrillic block uses a layout based on ISO-8859-5.