A bell at the Yeon-bog-jeol* 演福寺 Temple in Gae-seong 開城, cast by a Mongolian artisan in the second year of King Chung-mog-wang 忠穆王 (1346 A. C.), is of great importance from an historical and philological point of view. The existence of the bell was made known to scholars more than sixty years ago. The identification of the portions of Sanskrit inscriptions, however, has until recently caused much confusion. We have now been able to identify the Sanskrit texts cast in the Lañ-tsha and Tibetan scripts. One is a complete text of the Sanskrit version of the Uṣṇīṣavijiya-dhāraṇī, long a popular mantradhāraṇī among Buddhists, particularly in East Asia. Traditions have arisen from its use, and it has been transmitted in many versions into the scripts of the India, Tibetan, Chinese, Mongolian, Uigur and other languages. In the present article, it is not our intention to compare all the widespread and complicated materials, but rather to give detailed bibliographical information. An extremely interesting fact about the inscriptions on the bell at Yeon-bog-jeol is that it is exactly the same as the inscription found in the wallet the Chü-yung-kuan 居庸關, which is believed to have been completed around the same time. We think, therefore, that this was the authorized version of the U* in the Yüan dynasty. The Sanskrit inscriptions in Lañ-tsha script include a dhāraṇī to the Tathāgata Vairocana of the Garbhadhātu, a repetition three times of “O○ maṇi padme hu○, and dhāraṇī to the Bodhisattvas Samantabhadra and Mañjuśrī. The dhāraṇīs in Tibetan (dbu-can) script are again a repetition of those to the five Tathāgatas (Vairocana, Akṣobhya, Ratnasaṃbhava, Amitabha and Amoghasiddhi) in the Vajradhātu, followed by those to Avalokiteśvara-Tārā, Bodhisattvas Samantabhadra and Mañjuśrī and Vidyārāja Caṇḍamahāroṣaṇa (Acala). *Yasukazu SUEMATSU plans to publish a complete study on Yeong-bog-jeol in the future.