Polarized far- and mid-infrared reflectance spectra were measured at room temperature for the new mineral species jarandolite, CaB3O4(OH)3, for the two principal directions. Thirty three vibration modes for E⃗||c⃗ and 32 for E⃗⊥c⃗ were observed and analysed numerically. Symmetry analysis predicts 41 E⃗|| c⃗ and 40 E⃗⊥c⃗ vibration modes that include lattice and O–H modes. Mode assignment was made based on the structure of jarandolite. The values of the mode frequencies (ωTO), the damping factors (γ) and the oscillator strength (S) of each oscillator were obtained by fitting to a Lorentz model.