Two isostructural lanthanide-based MOFs [Ln(HL)L]·H2O (1-Ln, Ln = Eu, Dy, H2L = 5-((pyridin-4-ylthio)methyl)isophthalic acid) were successfully obtained via the solvothermal reaction. 1-Eu exhibits high fluorescence quenching efficiency for C2O72- and Fe3+, which can be potentially used as a luminescent probe; 1-Dy behaves as a typical single-molecule magnet with an energy barrier (ΔUeff) of 54(2) K.