In order to obtain the suitable phase change material (PCM) with low phase change temperature and improve its heat transfer rate, experimental investigation was conducted. Firstly, different mass ratios of lauric acid (LA) and stearic acid(SA) eutectic mixtures were prepared and characterized by differential scanning calorimetry (DSC). Then, the performance of eutectic mixture during charging process under different fin widths in vertical condition, and performance during charging and discharging processes under different inlet temperature heat transfer fluid (HTF) in horizontal condition were investigated, respectively. The results revealed that the LA-SA eutectic mixture had the suitable phase change temperature and desired latent heat for low-temperature water floor heating system. Wide fins and high inlet temperature HTF significantly enhanced the transfer rate and decreased the melting time.