A family of polyoxo(alkoxo)lanthanide cluster {Ln<sub>15</sub>} [Ln = Eu (<strong>1</strong>), Gd (<strong>2</strong>), Tb (<strong>3</strong>)] was successfully isolated via the simple hydrolysis reaction of lanthanide metal ions in the presence of tricine ligand. X-ray diffraction analyses revealed the {Ln<sub>15</sub>} display a wheel-like structure with a <em>µ</em><sub>5</sub>-chloride anion as template. Interestingly, each analogue shows distinctive function based on the different Ln(III) ions. The complexes <strong>1</strong> and <strong>3</strong> in solid state emitted the characteristic fluorescence of Eu(III) or Tb (III). The fluorescence lifetimes of <sup>5</sup><em>D</em><sub>0</sub> excited state for <strong>1</strong> and <sup>5</sup><em>D</em><sub>4</sub> excited state for <strong>3</strong> were tested and the values were 890 and 250 μs, respectively. For gadolinium analogue <strong>2</strong>, it exhibits magneto-caloric effect at ultralow temperatures with a maximum −Δ<em>S</em><sub>m</sub> value of 29.9 J·kg<sup>−1</sup>·K<sup>−1</sup> at 3 K and 7 T.