Abstract. This study examines the impact of ionizing radiation, particularly alpha particles, on human cells and molecules, with a focus on DNA damage. Alpha particles, although unable to penetrate the skin, pose significant health risks when inhaled, swallowed, or entered the body through a cut, causing severe damage to sensitive living tissue. The experiment involved measuring alpha particle interactions with human cells, revealing that even low doses of radiation can cause significant biological changes, including mutations that may lead to cancer in the current or future generations. According to the comparison of the energy of radio-active radiation, alpha rays cannot pass through ordinary paper. Accordingly, in our experimental procedure and method, we first record alpha particles without radio-active nucleus, and then we use radio-active nucleus that emit alpha rays. Has taken into consideration. According to the relevant data, we have drawn graphs and obtained alpha ray energy in air E_(∝max)=3.407 Mev and distance R_0=1,99mm.The results indicated that alpha particles induce DNA double-strand breaks (DSBs) in the nuclei of peripheral blood mononuclear cells (PBMCs), underscoring the necessity for stringent radiation protection measures. This study highlights the critical need for understanding radiation-induced damage mechanisms to develop effective prevention and treatment strategies for radiation-related health issues.