Aims and objectives: This study investigated how Chinese learners of English represent spatial metaphorical concepts when processing Chinese and English kin terms that differ in lexicalization, and whether English learning influences the conceptualization of Chinese kin terms. Methodology: Using a semantic judgment task and eye-tracking technology, the study investigated 70 Chinese high/low-level English learners’ spatial metaphorical cognitive pattern of “elder-up junior-down” and “patrilineal-inside maternal-outside” in Chinese and English contexts, and compared the Chinese spatial metaphorical cognitive pattern between high and low-level English learners. Data and analysis: Participants’ reaction time and eye movement data were analyzed using mixed-effects repeated-measures analysis of variance. Findings: Significant three-way interactions were found among seniority, position, and language in the up–down spatial metaphor experiment, as well as among kinship relation, position, and language in the inside–outside spatial metaphor experiment. The spatial metaphorical effects were observed only during the processing of Chinese kin terms, but not English kin terms. This suggests that cross-linguistic differences between Chinese and English kinship systems give rise to divergent cognitive patterns, which are flexible and sensitive to language context. In addition, a significant four-way interaction among seniority, position, language, and English proficiency was identified. Specifically, high-level English learners exhibited a weaker “junior-down” spatial metaphorical effect in Chinese kin term processing compared with low-level learners, indicating that L2 experience may influence L1 conceptualization in specific domains. Originality: Few studies have explored how second language learners represent concepts that are encoded differently across languages, or whether advanced learners retain native-like conceptual patterns after attaining high L2 proficiency. Significance: These findings contribute to the linguistic relativity hypothesis by revealing how language influences cognition through bilinguals’ metaphorical representations of kinship. The study offers valuable insights into bilingual conceptual organization.