Abstract Purpose: Monotherapy with eribulin or gemcitabine has been found to be moderately effective in treating soft-tissue sarcomas (STS). In this study, we evaluated the efficacy and safety of eribulin–gemcitabine combination therapy for the two most common histologic types of STS, liposarcoma and leiomyosarcoma. Patients and Methods: In this nonrandomized, multicenter, phase II study, we included patients with progressive disease who had received one or two courses of chemotherapy that included doxorubicin. Patients were administered 1.4 mg/m2 eribulin and 1,000 mg/m2 gemcitabine on days 1 and 8 every 3 weeks. The primary endpoint was progression-free survival rate at 12 weeks (PFSR12wks), with null and alternative hypotheses of PFSR12wks ≤20.0% and ≥40.0%, respectively. Exploratory biomarker analyses with next-generation sequencing (NGS) were performed on pretreatment tumor samples. Results: Among the 37 patients included, the overall PFSR12wks was 73.0%, achieving the primary endpoint. The objective response rate, disease control rate, median progression-free survival, and median overall survival were 16.2%, 78.4%, 5.6 months, and 31.9 months, respectively, without differences according to histologic type. New safety signals and treatment-related deaths were not documented. NGS-based transcriptome analysis revealed that functional enrichment in the TGFβ pathway was mostly associated with a poor outcome, whereas single genetic alterations largely failed to predict treatment outcome. Conclusions: Eribulin–gemcitabine combination therapy showed promising activity and an acceptable safety profile in patients with liposarcoma or leiomyosarcoma. Gene expression profiling with pathway enrichment analysis would have possibilities to have predictive value for survival outcome, necessitating further investigation to confirm.