High blood insulin levels, insulin resistance (IR), and obesity are components of metabolic syndrome (MetS). The literature has indicated a high risk of breast cancer in patients with MetS. However, no studies have been conducted evaluating the relationship between breast cancer-related lymphedema (BCRL), one of the most frequently encountered postbreast cancer treatment conditions, and IR. Therefore, the aim of this study was to evaluate whether there is a relationship between BCRL and IR. A total of 28 patients diagnosed with breast carcinoma were included in this preliminary study. Patients were divided into BCRL ( = 15; mean age: 55.2 ± 11.2 years) and non-BCRL (control) groups ( = 13; mean age: 55.17 ± 6.57 years). Body mass index (BMI), waist and hip circumference, and fasting blood glucose and blood insulin levels of all patients were recorded. The Homeostasis Model Assessment (HOMA) test was used for the calculation of IR measurement with a value of 2.5 taken as an indicator of IR. Parameters were compared between groups. BMI, waist circumference measurements, blood insulin, and HOMA-IR levels were statistically significantly higher in the BCRL group than the control group ( 2.5 were found in 14 patients in the BCRL group. In the control group, only three patients had IR based on HOMA-IR criteria ( = 0.000). Hip circumference measurements and fasting blood glucose levels were similar between the groups ( > 0.05). BCRL appears to be associated with waist circumference, fasting blood insulin level, and HOMA-IR levels. In routine clinical practice, evaluation of IR may be important in the follow-up of this patient population.