<p>To gain a deeper understanding of the historical changes in climate means and extremes over recent decades in Vietnam’s Mekong Delta (VMD), this study employed a multi-temporal trend analysis methodology. Non-parametric statistical trend tests, including Sen’s slope estimator, as well as classical and modified Mann-Kendall tests were applied to all possible periods with varying beginning and ending times. The outcomes consistently indicate progressive warming trends, with detectable trends at 30-year scales or more estimated to be around 0.04–0.49&#xa0;°C per decade. Regarding rainfall trends, the outcomes reveal much less coherent patterns across stations and periods analyzed. Trends estimated for long-term periods (record length of 30 years or more) were mainly weak and statistically insignificant, ranging from approximately 0.2–6.9% per decade for stations characterized by increasing trends in annual rainfall and from approximately − 0.1% to -4.5% per decade for those exhibiting declining trends. Meanwhile, time-varying trends at shorter-term time scales appeared to be more mixed with higher magnitudes, and also exhibited alternating increasing and decreasing trend behaviors or even a reversal of the dipole-like pattern. These findings highlight the sensitivity of time-varying trend patterns to the considered periods in terms of trend direction, magnitude, and statistical significance. This study also addressed potential relationships between El Niño-Southern Oscillation (ENSO) and interannual variability of rainfall anomalies based on correlation analysis. The outcomes reveal significant linkages between ENSO and rainfall variations in the VMD. Overall, this study provides more illuminating insights into the trend possibilities of climate means and extremes in the VMD.</p>