This study investigated the effect of pH and contact time on the removal efficiency of heavy metals, including chromium (Cr), nickel (Ni), and lead (Pb), from sterilized wastewater using dried Cladophora biomass. The experiments were conducted at three pH levels (5.5, 7, and 10) and different contact times (2, 6, and 24 hours), using wastewater matrices supplemented with selected heavy metals under controlled conditions. The results demonstrated that both pH and contact time significantly influenced the removal efficiency of all tested metals. Increasing the pH from acidic (5.5) to alkaline conditions (10) led to a marked improvement in removal efficiency. The highest removal rates were consistently observed at pH 10, reaching up to 97.14% for Cr, 88.92% for Ni, and 94.21% for Pb after 24 hours of contact time. Similarly, extending the contact time enhanced the removal performance at all pH levels, indicating a time-dependent biosorption process. Chromium exhibited the highest removal efficiency across all conditions, followed by lead and nickel. Overall, the findings confirm that alkaline conditions and prolonged contact time play a crucial role in optimizing heavy metal removal. The use of sterilized wastewater provides a controlled yet realistic system, demonstrating the effectiveness of dried Cladophora biomass for potential application in wastewater treatment.