Marine clays are often treated as problematic soil owing to their soft consistency and poor strength. Many times, the coastal and offshore structures founded on this clay are subjected to excessive settlements and failures. Marine clays are largely improved using various stabilization techniques which mostly include the use of conventional binders such as cement and lime. However, these conventional binders pose serious environmental concerns, hence the need for alternate binders for the improvement of marine clays arises altogether. On the other hand, construction demolition wastes, or CDW, are materials and debris from building demolition, restoration, and construction operations that are being generated at an alarming rate from various construction and demolition projects. The irrational disposal of CDW leads to a serious impact on the environment. As a measure to tackle the above-mentioned concerns, a study is conducted that investigates the possible use of recycled crushed concrete powder (CCP) derived from CDW as a potential binder for stabilizing marine clay through alkali activation of the soil-binder system. A comparative analysis of the effect of alkali-activated and non-activated crushed concrete powder as a binder on the strength development of marine clay is carried out. Microstructural examination using SEM-EDAX and TGA was performed. The CCP content was varied from 0 to 15% (0, 5, 10, and 15%) and the activation was achieved using the alkaline media consisting of 10 M concentration (0.4%, 0.6%, and 0.8%) of sodium hydroxide (NaOH) solution. The residual hydration of CCP and the alkali activation improved the unconfined compressive strength to an order of 381.07% & 394.03% with optimum binder combination of CCP 15% and 0.8% 10 M NaOH when cured for 7 and 28 days, respectively. The rate of increase is higher for the first 7-day period.