This qualitative study utilizes a heteroglossic perspective and discourse analysis methodology to examine why and for what purposes three Korean-American third-graders engaged in translanguaging practices while writing in a Korean heritage language(HL)classroom in the U.S.translanguaging refers to bilingual speakers’natural strategy when they utilize their full language linguistic repertoires from their two languages.In performing the analysis of translanguaging purposes,I categorize the students’written translanguaging purposes into four categories:sociolinguistic,metalinguistic,sociocultural,and metacognitive.The findings show that the emergent bilingual students utilize their linguistic resources from both their languages through translanguaging,and their translanguaging demonstrates their sociolinguistic competence,metalinguistic awareness,sociocultural understanding,and metacognitive insight.The fluid way that the students translanguaged while writing suggest that they were employing their integrated linguistic resources,rather than utilizing each language separately to write.The findings substantiate the use of heteroglossic perspective to explain bilingual students’utilization of two languages while writing.