The aim of this thesis is to define the audit in general and to define its meaning and essence. Documents obtained from the company demonstrated the method of implementation of internal audit. On the basis of these documents, the internal audit results for the years 2013 and 2014 were evaluated by individual departments and by the overall results. Based on the findings, the company was recommended the establishment of an internal audit of the accounting. Questionnaires were sent to a sample of companies in the South Bohemia. The questionnaire investigated whether the company has established an internal audit, how often they perform it, which person performs an internal audit, on what action the internal audit is focused and whether the empl...