RS-232 (בעבר EIA-232 ולפני כן EIA RS-232, כאשר RS הם ראשי תיבות של Recommended Standard, דהיינו "תקן מומלץ") הוא תקן תקשורת להעברה טורית של מידע בינארי בין מכשיר המשמש כמקור המידע (Data Terminal Equipment ,DTE) ומכשיר המשמש כקולט המידע (Data Circuit Equipment, DCE).
In telecommunications, RS-232 is a standard for serial communication transmission of data. It formally defines the signals connecting between a DTE (data terminal equipment) such as a computer terminal, and a DCE (data circuit-terminating equipment, originally defined as data communication equipment), such as a modem. The RS-232 standard is commonly used in computerserial ports. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange, issued in 1997.