Q-switched lasers widely used in management skin diseases andsometimes its effect may be inadequate or associated withcytotoxicity. The current study aimed to investigate the effect ofQ-switched Nd:YAG laser upon cellular elements using in vitroexperimental model. Aqueous solutions of human albumin and purecalf thymus double strand deoxyribonucleic acid (ctdsDNA)irradiated with Q-switched Nd:YAG laser at different rates (1, 3 Hz)and time exposure (up to 60 seconds) using 532 nm (400 mJ) and1064 (1200 mJ) nm wavelength with fixed spot size of 4 mm. Theeffect of laser irradiation on the albumin solution also studied in thepresence of elemental salts of copper, zinc and iron.Q-switched laser irradiation at 532 nm produced albumin moleculedamage that potentiated by copper sulfate and variable effect withzinc sulfate. Iron salt stabilized the effect of laser irradiation uponalbumin molecule. The effect of laser irradiation at 1064 nm is lessthan that observed with 532 nm wavelength. ctdsDNA strands aremore susceptible to Q-switched Nd:YAG laser radiation whenexposed at 532 nm with pulse rate of 3Hz. It concludes that usingQ-switched Nd:YAG laser is safe upon the c