<p>Wood density is an important functional trait used to estimate forest biomass and carbon stocks. Its wider range of variations, such as inter- and intra-specific level, and within tree disparity, repeatedly invoke wood density as a potential source of variation in biomass estimation. We aim to (1) measure pith-to-bark wood density profiles in major mangrove tree species in the Sundarbans and (2) quantify the deviation in above ground biomass (AGB) estimations by comparing the method that ignores wood density variation across the radius. Total 150 wood cores were collected from five widely distributed ecologically distinct mangrove species in three distinct salinity zones (low, medium, and high) in the Bangladesh Sundarbans. Wood density was measured for each 1&#xa0;cm long wood core segment from pith to bark. Among the light-demanding species, <i>Sonneratia apetala</i> and <i>Avicennia officinalis</i> showed a decreasing wood density trend from pith to bark while <i>Excoecaria agallocha</i> exhibited an increasing trend. Shade-tolerant <i>Xylocarpus moluccensis</i> displayed a decreasing wood density trend, whereas the most dominant <i>Heritiera fomes</i> unveiled less variable wood density from pith to bark. Wood density significantly decreased with increasing slenderness ratio in light-demanding species. Shade-tolerant species had a significantly higher mean wood density than light demanders. Similarly, the mean wood density was significantly higher in the high saline zone for the studied species, except <i>S. apetala</i> and <i>A. officinalis</i>. Ignoring radial variation, inner wood density underestimated AGB (~ 7% ha⁻¹) while outer wood density overestimated AGB up to ~ 5% ha⁻¹. Similarly, wood density from the repository overestimated AGB up to ~ 7% ha⁻¹. This study suggests to consider species-specific radial wood density variations to increase the accuracy of mangrove biomass estimations. Furthermore, these preliminary results pave the avenue for a b</p>