The purpose of this study was to examine the relationship between dominating conflict management strategy and effectiveness of multinational oil and gas companies in Nigeria. The study adopted the cross-sectional research survey design. Primary data was generated through structured questionnaire. The population of the study was the five (5) multinational oil and gas companies registered with the Department of Petroleum Resources. Since the population of five (5) multinational Oil and Gas producing companies in Nigeria was relatively small, the entire population was studied as a census and in line with the unit of analysis which is at the macro level, the questionnaire was distributed to the elements from the population was used as the participants and in line with the unit of analysis which is at the macro level, the questionnaire was distributed to ten (10) managers of the five (5) multinational oil and gas producing companies in Nigeria, bringing the total number to fifty (50) respondents. The category of managers included in the study were Directors, General Managers, Deputy General Managers, Divisional Managers and Deputy Divisional Managers. The reliability of the instrument was achieved by the use of the Cronbach Alpha Coefficient with all the items scoring above 0.70. The hypotheses were tested using the Spearman’s Rank Order Correlation Coefficient. The tests were carried out at a 0.05 significance level. Findings from the data analysis revealed that, there is a significant negative relationship between negotiating conflict management strategies and effectiveness of multinational oil and gas companies in Nigeria. Therefore, the study concluded that, the adoption of dominating conflict management strategy was negatively related to effectiveness in multinational oil and gas companies in Nigeria. Thus, the study recommends that multinational oil and gas companies should avoid using dominating strategy unless it is the only strategy that can fit the situation. This is because the findings revealed an inverse correlation between multinational oil and gas companies’ effectiveness and dominating strategy. Keyword: Conflict, Conflict Management Strategies, Effectiveness, Dominating, Growth Rate, Innovation Market Share