<p>Deltamethrin (a pyrethroid) and acetamiprid (a neonicotinoid) are widely used insecticides that have raised increasing concerns due to their potential toxicity. This study aimed to investigate their cytotoxic, morphological and molecular effects on normal (Thle-2) and cancerous (HepG2) human liver cell lines, as well as their interactions with key antioxidant-related enzymes. IC₅₀ values were determined using XTT assay following 24- and 48 h exposures to each compound individually and in combination. Cell motility was evaluated using wound healing assays, while oxidative stress-related gene expressions (<i>CAT</i>, <i>SOD1</i>, <i>GSTK1</i>) were analysed by qRT-PCR.</p><p>In Thle-2 cells, <i>CAT</i> and <i>GSTK1</i> expression significantly decreased after acetamiprid exposure (p &lt; 0.05). In HepG2 cells, <i>GSTK1</i> expression decreased with individual treatments but increased significantly under combined exposure compared to deltamethrin alone (p &lt; 0.05). Moelcular docking analysis revealed that deltamethrin exhibited stronger binding affinities with antioxidant ezymes, particularly SOD1 (−8.1 kcal/mol) and CAT (−8.0 kcal/mol), suggesting a higher potential for enzyme inhibition. In contrast, acetamiprid showed moderate affinities, with the lowest energy for CAT (−6.8 kcal/mol). ProTox predictions indicated moderate hepatotoxic, neurotoxic, and respiratory toxic potentials for deltamethrin, whereas acetamiprdi displayed a generally loe toxicity profile. Overall, these results suggest that both compunds modulate antioxidant defense mechanism and induce oxidative stress responses, with differential toxicity between normal and cancerous liver cells.</p>