It is well documented that resistance exercise can be performed by patients with breast cancer-related arm lymphedema. The aim of this pilot study was to evaluate the feasibility and safety of a 12-week self-administered weight lifting program for arm and shoulder, and its influence on arm lymphedema status, upper extremity muscle strength, and disability. Twenty-three patients with breast cancer-related arm lymphedema performed the program 3 times/week. The weight resistance levels were individually adjusted for shoulder flexion and adduction, and elbow extension and flexion corresponding to a repetition range of 8-12 repetition maximum. A log book was used to evaluate adherence to the program, wearing of compression sleeve and perceived exertion. Measurements were performed before a 2-week control period without intervention, and before and after intervention, and with arm volume measurements every fortnight to check for adverse events. Results revealed no significant changes during the control period. Adherence to the intervention program was excellent, and two adverse events were registered during the first weeks. After intervention, an increase of shoulder and arm strength (measured by an isometric muscle strength device) was found in all exercises (p = 0.001-0.003). A reduction of excess volume was shown, in ml (p = 0.03) and percentage (p = 0.005), measured by water displacement method. A tendency towards reduction (p = 0.07) of fat tissue in the upper arm (n = 10) in both arms was found measured by MRI. In this pilot study, we concluded that a home-based weight-lifting program performed by patients with breast cancer-related arm lymphedema is feasible and safe providing that the program includes regular follow-up for safety.