In this paper, we describe the designing, recording and checking procedures of a multi-accented Mandarin speech database, and present benchmark evaluation of this database. The database was recorded in 6 cities in China, containing 1200 speakers’ accented Mandarin speech of continuous digits, isolated words and sentences. In total, 520k utterances (572.5 hours) were collected. We perfrom the intra-accent and cross-accent evaluations, together with the evaluation of a multi-accented acoustic model trained from the whole database. The database is a phonetically rich, gender-balanced and accent-balanced database, which could serve as the basic material for accented Mandarin recognition research, and it could also be used for creating real automatic speech recognition products for users with different accents. Keywords: Mandarin, speech database, multi-accented