Foreign nationals studying English as a Second Language (ESL) in the Philippines encounter and learn Philippine English (PhilE), a norm-developing, Outer Circle variety of English (Bolton, 2008; Kachru, 1992) that has undergone various indigenization and nativization processes (Borlongan, 2011; Schneider, 2003), most notably in its phonology. Recent contributions to Philippine-based ESL and Second Language Acquisition research have particularly paid attention to language teaching and pedagogy, language ideologies, and foreign learners’ perceptions of and attitudes towards PhilE. In this study, I attempt to advance research by studying L1 and L2 speech production patterns and sociolinguistic perceptions of PhilE among Korean ESL learners. Koreans account for one of the largest number of foreign students enrolled in Philippine education institutions (D.-Y. Kim, 2015; Miralao, 2007), making them an ideal case to study. This thesis presents perhaps the first study that analyzes sociophonetic variation in second language acquisition in the Philippines. PhilE is a ‘non-native’ variety of English with a distinctive two-way stop system characterized by negative-to-short Voice Onset Time (VOT). This type of phonation feature is not common among native Korean speakers, whose L1 involves a three-way stop system combined with a significant degree of tonal/vocalic interaction (to achieve maximal phonemic contrast). Because the two stop systems are quite dissimilar from one another in terms of consonantal and tonal/vocalic contrast, Korean students who exhibit varying lengths and/or degrees of linguistic exposure to PhilE, and encounter different linguistic experiences during their L2 learning, would be expected to exhibit varying degrees of or changes to their categorical assimilation of L1 and L2 sounds (Flege, 1987, 1995) and phonetic drift patterns (Chang, 2012) in their interlanguage.