The aim of this study is to determine the effect of operating expenses on performance and growth in the petroleum and chemical industry. Operating expenses include research and development (R&D), marketing and administrative expenditures. Determining the distribution of these expenses in this industry an important issue. The data obtained from companies operating in the petroleum and chemical industry were analyzed using two separate models. Within the scope of research, it was determined that R&D expenditure has no significant effect on performance and growth. Marketing expenditure negatively affects performance and has no significant effect on growth. Finally, it was concluded that administrative expenditure has a significant positive effect on both performance and growth. These results indicate that ineffective R&D and marketing expenditures in this industry should be avoided. On the other hand, in terms of management function, it explains that expenditure should be shifted to the areas that will contribute, especially towards the future. Contribution/Originality: This study contributes to the existing literature by examining the effect of the operating expenses on firm growth and performance. Operating expenses include R&D, marketing and administrative expenditure. The results of the study provide guidance on operating expenses for companies that want to increase their performance and growth.