It is narrated from Hazrat Ubadah bin Samit (may Allah be pleased with him) that I heard the Noble Prophet (peace and blessings be upon him) say: The prayer of that person is not valid who cannot recite Surah Al-Fatihah.
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 22743