The experiment was undertaken to investigate the retention of 10% Chromated-Copper-Boron (CCB) solution (2:2:1) in Kala-koroi (Albizia lebbeck) (L.) Benth. wood applying soaking as well as diffusion method. The assessments were applied for 5, 7, 9 and 11 days for both the method. Retention was recorded 1.96 kg/m3,11.78 kg/m³,12.92 kg/m³ and 13.61 kg/m³  in A. lebbeck wood where soaking method applied. Moreover, retention was found 5.22 kg/m³, 6.43 kg/m³, 7.32 kg/m³ and 12.36 kg/m³ in A. lebbeck wood when diffusion method applied. In case of both methods the highest retention was recorded 13.61 kg/m³ and 12.36 kg/m³ for 11 days. Considering the Standard of Bangladesh Standards and Testing Institution (BSTI), i.e., 13.61 kg/m³ and 12.36 kg/m³ retention can meet the suitability of the study.