Introduction. The rupture of knee ACL is on the third position of all ligament ruptures in the knee and on the first position of which is healed by operation. The clinical status tested by orthopedic test (history, knee stabilization, goniometrical range of motion) is the main reason to choose the type of healing procedure. The evaluation of the clinical status is convergent to subjective feeling of quality of life and low level of pain. The aim of the paper was to determine whether the improvement of physical fitness and stabilization of the knee will have influence on the quality of life of the patients. Materials. The aim of the paper was carried out based on the clinical material, collected in the years from 2008 to 2010. For the study there were classified 201 patients with the diagnosed broken front knee ligament. All these people were treated surgically. After the operation the patients underwent the rehabilitation clinic Reha-probatus in Cracow. Methods. The patients were examined twice, before the surgery and after the surgery followed by post-surgery rehabilitation. To observe the changes in the parameters of quality of life, we used the following tests and questionnaires: 1) The SF-36 questionnaire to evaluate the patients quality of life; 2) Clinical tests (ROM of knee joint, Lachman test, Pivot shift test and symptoms evaluation test – part of the questionnaire IKDC). Results. Evaluations of range of motion ROM of the knee joint have an influence on psychological health, pain and patients health at all. Additionally increasing knee ROM have an influence on physical health. The rest of statistically significant influences are applying rotation stability of knee joint on social life, pain and health at all and anterior stability on physical and psychological health. Conclusions. The improvement in the areas of life quality, especially mental, physical, social and pain depends on the improvement of the orthopaedic test results concerning the stability and scopes of mobility of the treated knee joint after the break of the anterior cruciate ligament. Decrease of experiencing the symptoms of the broken ACL ligament of the knee joint has impact on the improvement in experiencing in terms of physical and mental health. The improvement of the scope of extension of the treated knee joint has impact on the widest range of areas of life quality improving them in the greatest number of percentage of the examined patients due to the broken ACL ligament.