Percutaneous coronary intervention (PCI) is a non-surgical invasive procedure to treat coronary artery occlusion. The quality of life (QoL) is a way to measure the impact of illness and additionally its treatments to traditional measures of clinical outcomes. The aim of the present study was to explore the levels of QoL pre-PCI, 6 and 12 months after PCI, as well as the factors associated with the QoL pre-PCI. In the present study, 100 patients undergoing PCI were enrolled. Data were collected through the completion of the SF-36 Health Survey (SF-36), which included participants' characteristics. The statistical significance level was p < 0.05. Patients had moderate levels of QoL at baseline, with a median general health score of 45 (IQR: 30-65). A gradual statistically significant increase in scores was observed in all subcategories of the patients' QoL at 6 and 12 months after PCI (p < 0.001). A greater increase in scores was observed in physical functioning, physical role, emotional role and social functionality. In terms of the pre-PCI phase, it was found that physical functionality was statistically significantly associated with educational level (p = 0.005), occupation (p = 0.026) and whether the patients had children (p = 0.041). The physical and emotional role was significantly associated with gender (p = 0.046 and p = 0.040) and educational level (p = 0.030 and p = 0.001). Energy-fatigue was significantly associated with gender (p = 0.001), age (p = 0.028), marital status (p = 0.001), educational level (p = 0.001), whether the patients had children (p= 0.012) and other diseases (p = 0.001). Emotional well-being was significantly associated with family history of coronary artery disease (p = 0.011) and the frequency of physical exercise (p = 0.001). Social functioning was significantly associated with gender (p = 0.033), marital status (p = 0.034) and educational level (p = 0.002). Pain was not found to be significantly associated with patients' demographics. General health was significantly associated with gender (p = 0.003), age (p = 0.043), educational level (p = 0.001), other diseases (p = 0.005) and the frequency of physical exercise (p = 0.001). Information about the QoL of PCI and its determinants is important to define an effective and comprehensive care plan.