Cost Audit represents the verification of cost accounts and check on the adherence to cost accounting plan. This article focuses on various provisions regarding applicability of cost audit rules to various companies, how cost auditor is appointed, how remunearation of cost auditor is determined etc. Cost Audit ascertain the accuracy of cost accounting records to ensure that they are in conformity with Cost Accounting principles, plans, procedures and objective. These Rules shall apply to every company covered under the Companies (Cost Accounting Records) Rules, 2013 under Sub-Section (1) of Section 148 and which have such amount of net worth or the value of the turnover made by the company from sale or supply of all products or activities during the immediately preceding financial year. Every company as specified in Rule 3 above shall, within one hundred and eighty days of the commencement of every financial year, appoints a cost auditor