Background and Objectives: Diabetic complications represent a major healthcare challenge globally. The Kingdom of Saudi Arabia has one of the highest prevalence rates, yet comprehensive data on complication profiles from southern regions remain limited. This study characterizes the spectrum of diabetic complications and identifies associated risk factors in the Najran region of southern Saudi Arabia. Materials and Methods: A hospital-based retrospective analysis of 500 diabetic patients from two major public hospitals in the Najran region was conducted using electronic medical records from January 2022 to December 2023. A systematic sampling approach was adopted. Type 1 diabetes (T1D), Type 2 diabetes (T2D), and their complications were defined using standardized criteria. Data extraction utilized a validated proforma, and analysis employed SPSS version 20. Separate analyses were conducted for T1D and T2D, with multivariable logistic regression identifying independent predictors of complications (p < 0.05). Results: The study included 200 T1D (median age 14.0 years, IQR 3.0) and 300 T2D patients (median age 23.0 years, IQR 7.0). The high proportion of T1D patients (40%) reflects the hospital’s role as a specialized pediatric and young adult diabetes referral center. Among T1D patients, 63.5% (127/200) developed complications, predominantly microvascular, whereas 50.0% (150/300) developed complications in T2D. Poor glycemic control was the strongest predictor of complications in both groups (p = 0.01). Rural residence significantly increased complication risk in T2D patients (p = 0.02). Disease duration showed differential effects; complications appeared earlier in T1D (median 6.5 years) versus T2D (median 8.2 years). Conclusions: This study gives the first comprehensive analysis of diabetic complications from southern Saudi Arabia, revealing distinct patterns and associated risk factors. The findings provide regional perspective on diabetic complications in Najran, highlighting the importance of early glycemic control and equitable healthcare access. The results are not intended for nationwide generalization, rather, they point to the need for region-specific diabetes management strategies.