Waterlogged wood artifacts deteriorate as salts and dissolved substances accumulate during prolonged submersion or burial. After excavation, salts may crystallize and cause damage. Desalination is essential for conservation. This study examine water quality during desalination and relationships variables influencing desalination in waterlogged wood from the Phanom-Surin shipwreck, Samut Sakhon Province, Thailand. Total of 27 samples were immersed in RO water at a water-to-weight ratio of 10:1, a biocide (KATHON CG, 0.02% w/v). The experiment 2 batches: (1) 24 samples with weekly water replacement until electrical conductivity (EC) decreased to ≤100 µS/cm and (2) 3 samples without water replacement to evaluate closed-system conditions. Water quality parameters including water temperature, EC, salinity, pH, TDS, turbidity and COD were monitored weekly. Data distribution was tested using the Shapiro–Wilk test and relationships were analyzed using Spearman’s rank correlation. The quality of immersion water as follows: water temperature = 26.90±2.29 °C, TDS =0.12±0.06mg/L,salinity=0.01±0.03ppt,pH =4.25±0.55, turbidity = 1.21±0.72 NTU and COD= 18.76±15.56 mg/L. EC is sharply decreased during the first water replacement; from approximately 1,781.30 to 239.60 µS/cm, and remain constant throughout the experiment. Spearman’s correlation analysis revealed that EC was positively correlated with salinity (r=0.521, p<0.01), indicating that EC can reflect changes in dissolved salts in the immersion water. EC also showed positive correlations with COD (r=0.529, p<0.01), turbidity (r=0.548, p<0.01) and TDS (r=0.418, p<0.01). Similarly, salinity was positively correlated with COD (r=0.448, p<0.01) and turbidity (r=0.450, p<0.01). In contrast, pH showed strong negative correlations with EC (r=−0.906, p<0.01), COD (r=−0.600, p<0.01), turbidity (r=−0.586, p< 0.01) and salinity (r=−0.504, p<0.01). These relationships suggest that increases in dissolved ions, suspended particles and organic matter are associated with lower pH values in the immersion system. Overall, EC, pH, turbidity and COD can serve as key indicators for monitoring water quality and evaluating the desalination process.