Background: Injury to the medial collateral ligament (MCL) of the elbow has become increasingly common in sports, and the elbow is prone to contracture and ossification in trauma. Effective reconstruction of the MCL with reduction of irritation to the elbow has rarely been reported. This study introduces a minimally invasive elbow MCL reconstruction technique and evaluates the valgus stability. Methods: Eight fresh-frozen elbow specimens underwent reconstruction of the anterior bundle of the MCL (AMCL) first with the flexor carpi ulnaris fascia patches, followed by reconstruction of the posterior bundle of the MCL (PMCL) with the triceps tendon patches. The valgus angles of each specimen were examined in three stages as follows: intact MCL, reconstruction of the AMCL alone, and reconstruction of the MCL (including AMCL and PMCL). Finally, specimens were loaded to failure, and failure modes were recorded. Results: AMCL reconstruction alone had similar valgus stability at all testing angles (p = 0.080, 30° flexion; p = 0.064, 60° flexion; p = 0.151, 90° flexion; p = 0.283, 120° flexion) compared with the intact MCL, as did MCL reconstruction (p = 0.951, 30° flexion; p = 0.739, 60° flexion; p = 0.841, 90° flexion; p = 0.538, 120° flexion). More importantly, a significant difference existed between the MCL reconstruction and the AMCL reconstruction alone at 30° flexion (p = 0.043) and 60° flexion (p = 0.013) but not at the 90° flexion (p = 0.369) and 120° flexion (p = 0.879). The mean maximum failure torque of MCL reconstruction was 24.02 Nm at 90° elbow flexion. Conclusion: Both AMCL reconstruction alone and MCL reconstruction provided valgus stability comparable with the native MCL, and importantly, MCL reconstruction provided more valgus stability than AMCL reconstruction alone at 30° flexion and 60° flexion of the elbow. Therefore, the new MCL reconstruction technique might be a useful guide for the treatment of elbow MCL injuries or deficiencies.