Yes, Article 9 of the Saudi Labor Law requires that all data, records, files, and employment contracts must be in Arabic. This is the official language for all documentation required under the law or any ministerial decisions issued to implement it.
As an expat, it is strongly advisable to request a bilingual contract — Arabic alongside your preferred language (English, for example). While the Arabic version will be the legally binding one in any dispute, having a translated copy helps you understand exactly what you are agreeing to before signing.
If your employer provides you with a contract only in English or another language, be aware that this may not fully comply with the law. Ask your employer or HR department to provide the official Arabic version and, if needed, use a certified translator to verify that both versions match before you sign.
This is general legal information, not legal advice. For advice on your specific situation, consult a lawyer licensed in Saudi Arabia.