The thesis is focused on the application of audit procedures in the audit of financial statements and the audit of the balance sheet, profit and loss in a non-profit organization. In the first chapter we analyze the theoretical background of the issue and the concepts of audit. In the practical part, we conducted an audit in a real non-profit organization. We have used substantive tests to test the balance sheet and profit and loss account while concluding that the financial statements as a whole provide a true picture without material misstatement. Subsequently, we created an auditor's report with an unconditional opinion on the non-profit organization.