This study examines the economic assessment of some selected quarries operations in Ondo State, South-Western Nigeria. Ten quarries were visited in the course of this study and relevant data were collected using a well-structured questionnaire. All the companies share a total of 15.89x106 tons of estimated granite reserve. Estimated royalties generated by the Federal Government is N364,440 day-1. A total of 272 people are directly employed by the quarries, while 116 people are employed indirectly in the companies' communities. The study also revealed the effectiveness of each selected company based on their production and the pro?tability of each company. It was also found out that quarry operations in Ondo State are very pro?table and rewarding for investors but government should improve power supply to encourage investors and reduce the cost of operating the quarries.