Background Type 2 diabetes mellitus (T2DM) studies have a lengthy history. It is one of the world's most common illnesses, and in Jordan, it is prevalent. As the importance of minimizing the accompanying complications grows, this situation presents a formidable task. Self-efficacy, self-care, and the cumulative blood sugar index are just a few predictors of establishing a T2DM patient's quality of life. Purpose This study investigated the associations between diabetes self-efficacy, diabetes self-care, glycemic control, and quality of life among T2DM patients in Southern Jordan. Methodology This study used a cross-sectional correlational descriptive study design. The researchers used a convenience sampling technique to select the participants to obtain the goals. Results With scores ranging from 49.60 to 56.48 out of 100, the quality of life is strongly positively connected with self-care practices, self-efficacy, and HbA1c levels. Age, gender, a lack of education, divorce, and patients with various chronic diseases all suffer from a low quality of life. On the other hand, a higher and better quality of life is experienced by patients who have access to information, practice good self-care habits, have high self-efficacy, and have a high income compared to other patients. This holds true for all quality-of-life dimensions and total scores. Another promising finding is that the quality of life score as a whole has a p-value of p.001 in this study. Conclusions The study's summary revealed that T2DM patients in southern Jordan experience inadequate care, self-efficacy, and HbA1c control, leading to reduced quality of life. The total quality of life score is 52.39, which means a low quality of life level and increased complications. These issues stem from cultural norms, traditions, misconceptions, education, and economic factors. The study highlights the need to understand the region's disease prevalence and patient health status. Future interventions should focus on education, dispelling misconceptions, raising awareness, improving health literacy, patient follow-up, social empowerment, and group therapy to foster patient engagement.