Background: Refractive errors have occurred in many parts of the world, including in Indonesia, with different types of abnormalities, one of which is myopia which can be corrected with glasses and spherical contact lenses.

Aim: To determine the relationship between the level of knowledge of the installation and care of soft contact lenses in myopic patients.

Methods: This research method is Cross Sectional at Optik Metro, the number of samples is the total population, the research instrument is a questionnaire, the independent variable of this research is the level of knowledge while the dependent variable is the attitude and behavior of Care and Installation with Successful Use of Contact Lenses. This research has been approved by the Widya Husada STIKES Ethics Commission.

Results: The results of the study based on the number of sufferers and the distribution of refractive errors at Optik Metro from March 15-20, 2021, showed that the number of myopia patients who came was 13.0% with the type of treatment using soft contact lenses as much as 2.2%. There is a relationship between knowledge and attitudes of respondents with maintenance and installation behavior with successful use of LK with a significance value of 0.000 (p < 0.05).

Conclusion: It was concluded that the toric soft contact lens installation procedure was carried out in the right way by taking into account a good fitting assessment. It is necessary to provide education to increase knowledge and education on Care and Installation of Contact Lenses for all customers.

Keywords: Knowledge, Attitude, Soft LK, Myopia