Dr. O. A. Orji belongs to several scholarly society. Below are some of them.
| i) Member; Soil Science Society of Nigeria.ii) Member; Horticultural Society of Nigeria
iii) Member; Nigeria Environmental Society of Nigeria iv) Business Manager; ACTA AGRONOMICA NIGERIANA JOURNAL v) Member; International Union of Soil Science (IUSS) vi) Member; Institute of Professional Agriculturists of Nigeria vii) Member; Soil Science Society of America viii) Member; Agronomy Society of America ix) Member; Nigerian Institute of Soil Science |