Research problem: The purpose of the study was to explore the effects of national culture and medium type on first impression bias reduction in the context of job interview and performance appraisals. Research questions: (1) Does the evaluators' national culture affect first impression bias reduction? (2) Which medium type (text or multimedia) is more effective in reducing first impression bias? and (3) Does medium effect in reducing first impression bias vary with national culture? Literature review: The purpose of the literature review is to examine the current literature in the areas of national culture, medium type and first impression bias reduction, especially in a communication context. Researchers reviewed the discussions on first impression formation, and national culture theories, and the Media Richness Theory. For media, multimedia type was found to reduce first impression bias more than text medium type. For national culture, the literature review suggested that national culture dimensions (such as collectivism, assertiveness, and uncertainty avoidance) could possibly affect first impression bias reduction. Methodology: The researchers conducted a quantitative experiment with 407 students from a US university and a Chinese university, who majored in business-related disciplines. Researchers requested the treatment group participants to access performance bias cue. The participants then performed an initial appraisal of a manager based on Denison's leadership index. The participants then viewed the job interview of the manager, via different media, and performed the appraisal again. The performance appraisal data were collected via a website. The researchers used Analysis of Variance to analyze the data. Results and discussion: This study found that for our participants, national culture reduces first impression bias more than media. It identified that first impression bias reduction in US participants is significantly greater than that in Chinese participants, independent of media used. Regardless of national culture of media users, this study found that users using text medium were able to reduce first impression bias significantly more than users using multimedia. The implications of this study are that to reduce first impression bias in cross-cultural settings, managers and employees must adapt the channels and effort allocation for communication to national culture. Managers and researchers must understand that national culture is more important than media in reducing first impression bias. The limitations of the study were the use of student participants, and absence of national culture dimensions measurement. The study was conducted in only two national cultures. Future research could use employees as participants, measure national culture dimensions, and replicate the study in various national cultures.