Background: Among patients with non-ST-segment elevation myocardial infarction (NSTEMI) the presence of a bifurcation left main (LM) disease represents a particular subset graved by both clinical and technical challenges. We sought to assess the long-term outcomes of patients with NSTEMI treated either by single or double stent strategy, having an LM bifurcation culprit lesion. Methods: We retrospectively analyzed the procedural and medical data of consecutive patients referred to our center for NSTEMI due to complex LM bifurcation disease as the culprit lesion, treated using either single or dual stenting (provisional stenting, T or T-and-Protrusion (TAP), Culotte, and Nano-inverted-T (NIT)) techniques between January 2008 and May 2018. Target lesion failure (TLF) was defined as the composite of cardiovascular death, target-vessel myocardial infarction (MI), and clinically driven target lesion revascularization (TLR). Results: Four hundred and forty-five patients (54.1% males, mean age 70.3 ± 12.8 years, mean Syntax score 31.6 ± 6.3) were evaluated. Of these, 155 patients (34.8%) were treated using a single stent while the remaining were treated with a double stent strategy. After a mean follow-up of 37.1 months (IQR 22.1-39.3), TLF rate was 8.7% (n = 39): 5/155 (3.2%) in the crossover group; 10/53 (18.8%) in T/TAP group, 14/89 (15.7%) in the culotte group, and 10/148 (6.7%) in the NIT group of patients. Cardiovascular mortality rate was 2.9% (n = 13) while stent thrombosis was 0.89% (n = 4). On multivariate analysis dyslipidemia, Syntax score > 25, triple vessel disease, additional LM ostial, or LM body lesions and the use of Rotablator, were independent predictors of TLF. Conclusions: Either a single or double stent strategy resulted in low rates of TLF, cardiovascular death, and stent thrombosis in the long-term period in NSTEMI LM patients with contraindications or refusal of surgery. A single stent strategy appeared to have a slightly better outcome compared to a 2-stent strategy.