The consequence of good diabetic treatment depends on the patient’s commitment to a large degree. Noncompliance leads to inadequacy of metabolic control, which strengthens the advancement and speeds up diabetic complications. The study’s main goal was to assess the treatment noncompliance level among patients with type-2 diabetes mellitus (T2DM) in Bangladesh. This descriptive cross-sectional study was conducted at Medical Center Hospital, Chattogram, Bangladesh. The study included two hundred and fifty-nine patients with T2DM. Data regarding sociodemographic factors, patient’s characteristics, medication factors, physician-related factors, and noncompliance were collected using a pretested and structured questionnaire. Treatment adherence was assessed by Morisky Medication Adherence Scales (MMAS-8). Data analyses were conducted on SPSS v23.0 Software. The majority of the participants (56%) were in the 40–45 years of age group, followed by 32% in the older age group (≥60 years), and 62.5% of them were male. One hundred and sixty-eight (64.86%) patients were considered low adherent as per the response of the MMAS-8 scale (score <6), followed by 57 (22.0%) patients were regarded as high adherent (score 8) and 34 (13.13%) patients were considered medium adherent (score 6–7) to treatment. Observing the frequency distribution for noncompliance, financial concerns (32.3%), forgetfulness (27.7%), a busy daily schedule (17.7%), and fear of antihyperglycemic drug side effects were all identified as significant explanations. On multivariate analysis, participants aged 60 years or more, monthly family incomes of <30,000BDT or 30,000–50,000 BDT, smoking, and uncontrolled glycemic status showed higher chances of noncompliance than their counterparts. Patient counseling and awareness programs may enhance treatment adherence among people with T2DM. Our findings will help physicians and public health workers to develop targeted strategies to increase awareness of the same among their patients.