Communication skills are one of the most important competencies for 21st century global citizens. Our guiding presupposition was that socioscientific issues (SSIs) could be used as an effective pedagogical tool for promoting students' communication skills by increasing peer interactions, stimulating students' reasoning, and in constructing shared social knowledge. We implemented a SSI program on gene modification (GM) technology to 132 9th graders in South Korea and investigated to what extent this SSI instruction contributed to enhancing students' communication skills. Data sources included pre- and post-scores on the Communication Skills Questionnaire (CSQ), semi-structured interviews with the students and instructor, and classroom observations. The results demonstrated that SSI instruction could bring about a moderately large impact on students' ability to understand the key ideas of others and to value others' perspectives, as well as a marginal positive effect on developing active assertions. However, SSI instruction appeared to have a lesser impact on students' ability to develop shared understanding. Overall, this research indicates the potential that even a limited SSI classroom could have in terms of promoting students' communication skills in the context of their regular science class.