ABSTRACT Selection of purple waxy corn genotypes for high and stable anthocyanin content in corn cobs is important for breeding programs and anthocyanin production. The objectives of this study were to evaluate the effects of location, genotype and their interaction on anthocyanin content and antioxidant activities and to identify purple waxy corn genotypes with high and stable anthocyanin content. Five purple waxy corn and a white waxy corn genotypes were evaluated in a randomized complete block design with three replications at four locations with different elevations in Thailand . Location (L), genotype (G) and GxL interaction were significant for all characters. Waxy corn grown in Nakhon Ratchasima had the highest total anthocyanin content (TAC), cyanidin 3-glucoside (C3G), pelargonidin 3-glucoside (Pg3G), and peonidin 3-glucoside (Pn3G), DPPH radical scavenging activity of phenolics (DPPH) and Trolox equivalent antioxidant potential (TEAC). Genotype KNDM4 had the highest TAC, Pg3G, Pn3G and DPPH. Its regression coefficient (b i ) was close to one but it had the highest Sd 2 , indicating specific adaptation to favorable environments. KNDM4 genotype performed better than other genotypes at unfavorable environments for all studied traits. This information is useful for breeding programs and anthocyanin production from purple waxy corn. Keywords: Anthocyanin production, Different elevations, Favorable environments, Regression coefficient, Specific adaptation