The article analyzes the current state of the Ukrainian and world oil markets. The set of theoretical, organizational and methodological principles of accounting and auditing is clarified to clarify the methodological aspects of accounting and auditing of finished products and their sales. The organization of accounting and auditing of finished products is studied, the directions of improvement of accounting and auditing of finished products and the process of its sale at JSC “Ukrtransnafta” is determined. The analysis of financial and economic indicators of the enterprise showed that almost all indicators of the asset balance of JSC “Ukrtransnafta” during 2019–2020 have positive dynamics. Only the depreciation of fixed assets decreased by 9.8% (due to the purchase of new equipment), other current assets – by 24.5%, long-term receivables – by 19.67% and prepaid expenses – by 61.6 %%. During 2020 other non-current assets increased the most – by 422%, other current receivables increased by 300%, Cash and cash equivalents increased by 234%. Analysis of the structure of the balance sheet asset showed that non-current assets in 2019 amounted to 74.5%, and in 2020 – 81.6%, so non-current assets are the main assets of JSC “Ukrtransnafta”, among which fixed assets are 78.7% in 2019 and 81% in 2020, unfinished capital investments 19.9% in 2019 and 17.8% in 2020. During 2020 other long-term liabilities have undergone the greatest changes. They increased by 400%. Current accounts payable on advances increased by 204%, current income tax liabilities increased by 148%, current liabilities for goods, works and services increased by 110%. Negative dynamics was present in the following indicators: current liabilities in: insurance settlements – decreased by 17.9%, other current liabilities decreased by 16%. A study of the structure of liabilities of the balance sheet showed that the main share of liabilities is equity, in addition, its volume continues to grow: in 2019 equity is 83.2% of the balance sheet currency in 2020 – was already 85.9%. Long-term and current liabilities in 2018 was a little more than 8%, but in 2020. Great Danes increased to 9.5% and short-term decreased to 4.5%. Among equity, the main share in the structure is occupied by Capital in revaluations – 66.3% in 2019 and 62.8% in 2020, on the second position is additional capital – 21.3% in 2019 and 19% in 2020, on the third – retained earnings: 7% in 2019 and 13.4% in 2020. Indicators of net income and cost of goods in general increased during the study period from 2016 to 2020. Among the revenues of JSC “Ukrtransnafta” the main share falls on the income from the sale of goods and services, which averages 78% in recent years. Also quite a significant share of income of JSC “Ukrtransnafta” falls on other operating income, which on average for the period 2016–2019 is 14%, and 2020 – 21%. Analysis of the dynamics of other operating income showed that they grew the most in 2017 (almost 40 times), significantly increased in 2014 (138%) and in 2016 (90%). For internal use, “Ukrtransnafta” JSC proposed to improve analytical accounting for accounts 26 “Finished goods” and 70 “Sales income”, it is recommended to open third and fourth order accounts to these accounts to display information on the type of finished product and its sales. The main transformational adjustments that may occur depending on the characteristics of individual characteristics of finished products and their sales at JSC “Ukrtransnafta” are summarized. Improvement of accounting and audit of finished products and their sales of JSC “Ukrtransnafta” was carried out on the basis of network modeling of finished products and their sales at JSC “Ukrtransnafta”, as a result of which it was found that the duration of audit of finished products and its sales JSC “Ukrtransnafta” is 21 days, it requires 2 auditors. The efficiency ratio of auditors’ working time will be 50%. After the optimization of the location in time of the audit, it amounted to 58.93%, i.e. increased by 8.93% compared to the original version.