Background: Patient adherence to insulin therapy is one of the major challenges during the treatment of diabetes mellitus. Considering the dearth of investigations, this study aimed to determine the adherence pattern and factors linked with nonadherence among diabetic patients using insulin in Al-Jouf region of Saudi Arabia. Methods: This cross-sectional study included diabetic patients using basal-bolus regimens, whether they had type 1 or type 2 diabetes. This study’s objective was determined using a validated data collection form that included sections on demographics, reasons for missed insulin doses, list of barriers to therapy, difficulties during insulin administration, and factors that may improve insulin inaction adherence. Results: Of 415 diabetic patients, 169 (40.7%) were reported to forget doses of insulin every week. The majority of these patients (38.5%) forget one or two doses. Away from home (36,1%), inability to adhere to the diet (24.3%) and embarrassment to administer injections in public (23.7%) were frequently cited as reasons for missing insulin doses. The occurrence of hypoglycemia (31%), weight gain (26%), and needle phobia (22%) were frequently cited as obstacles to insulin injection use. Preparing injections (18.3%), using insulin at bedtime (18.3%), and storing insulin at a cold temperature (18.1%) were the most challenging aspects of insulin use for patients. Reduction in the number of injections (30.8%) and convenient timing for insulin administration (29.6%) were frequently cited as factors that may improve participant adherence. Conclusions: This study revealed that the majority of diabetic patients forget to inject insulin, primarily as a result of travel. By identifying potential obstacles faced by patients, these findings direct health authorities to design and implement initiatives to increase insulin adherence among patients.