Storage (G′) and loss (G″) moduli of low-moisture, part-skim Mozzarella cheese were determined at 10 and 20°C during 1 mo of refrigerated aging. At both temperatures, G′ was always greater than G″. Averaged over aging, G′ increased from 90 to 630 and G″ from 44 to 52 kPa at 10°C, and at 20°C G′ increased from 28 to 190 and G″ from 14 to 53 kPa for the frequency range 0.005-20 Hz. Averaged over frequency, both G′ and G″ decreased about 20% at 10°C and 25% at 20°C during aging. Relaxation spectrum, computed from shear relaxation data, was used to calculate the G. The calculated values of G′ were in good agreement with those determined experimentally. These data help predict and compare melting behaviors of such cheeses.