Ma Tovu (Hebrew for "O How Good" or "How Goodly") is a prayer in Judaism, expressing reverence and awe for synagogues and other places of worship.

The prayer begins with Numbers 24:5, where Balaam, sent to curse the Israelites, is instead overcome with awe at God and the Israelites' houses of worship. Its first line of praise is a quote of Balaam's blessing and is thus the only prayer commonly used in Jewish services that was written by a non-Jew. The remainder of the text is derived from passages in Psalms relating to entering the house of worship and preparation for further prayer (Psalms 5:8; 26:8; 95:6; and 69:14). In this vein is the prayer recited by Jews upon entering the synagogue; in the Western Ashkenzic rite, it is usually sung before beginning Maariv on Festivals, especially the second night of Yom Tov.