We experienced robotic-assisted total knee arthroplasty without lateral soft tissue release in Krackow Grade II valgus deformity. In 1991, Krachow et al. classified valgus knees into three types. The majority of cases (80%) were classified as Grade I. Flexion contracture of less than 10 degrees and passively correctable, with lateral soft tissue contracture.Grade II is Flexion contracture between 10 and 20 degrees, and passively non correctable with lateral soft tissue contracture, and elongation of the MCL, but functional. Grade III is Flexion contracture is greater than 20 degrees, and passively non-correctable, lateral soft tissue are tight, and the MCL are not functional after high tibial osteotomy. In a patient (77 years old female) with “ Krachow grade II valgus deformity ”, robotic-assisted surgery enabled: Correction without lateral soft tissue releases, Achievement of physiological alignment, and Stabilization of MCL allowed the use of a semi-constrained prosthesis rather than a constrained condylar knee.