Background: Reconstructive procedure following resection of large pelvic tumours around the hip joint remains a complex challenge. Methods: This study presents a retrospective case series of patients presenting with benign or malignant pelvic tumour for which an internal hemipelvectomy including the hip joint and subsequent reconstruction with a custom designed 3-dimensional printed titanium pelvic implant (3DPPI) has been performed between August 2013 and January 2018. Results: 15 consecutive patients with a median age of 33.9 years (IQR 26.4–72.2) and a median BMI of 20.7 kg/m² (IQR 19.0–33.3) were reviewed after median follow-up of 33.8 months (IQR 24.0–78.1). The majority of patients presented with a malignant tumour as their principal diagnosis ( n = 13, 86.7%). The median surgical time was 5.5 hours (IQR 4.5–8.5) and median peri-operative blood loss was 5000 ml (IQR 2000–10000). The median MSTS score at follow-up was 63.3% (IQR 51.7–86.7%). The median NRS in rest was 0.0 (IQR 0.0–5.0), the median NRS during activity was 2.0 (IQR 0.5–7.0) and the median HOOS-PS was 76.6% (IQR 67.9–91.0). 4 patients had implant-specific complications ( n = 4, 26.6%); 1 hip dislocation (Henderson type 1a), 3 structural complications (type 3a), 1 deep infection (type 4a) and 1 local tumour recurrence (type 5b). At follow-up, 4 out of 15 implants were classified as a failure, resulting in an implant survival rate of 73.3%. Conclusions: Acceptable peri-operative outcomes, functional results, complication rates and short-term implant survival can be achieved in a cohort of complex patients undergoing 3DPPI reconstruction after hemipelvectomy including the acetabulum.