Effective mass of phi mesons at finite temperature

The effective mass of phi meson at non-zero temperature is re-examined with an effective chiral Lagrangian. We find that the phi mass decreases with temperature but the effect is small compared to the result obtained from calculations using QCD sum rules. The leading contributions come from kaon loop corrections but vector meson contributions are also important as temperature increases. We discuss consequences of these changes to the phenomena of chiral phase transition in hot hadronic matter.