In view of the limitations or inadequacies of sole use of organic or inorganic fertilizers, hence, there is a dire need to critically appraise the potential of combined application of organic and inorganic fertilizers as a nutrient source to improve soil fertility, and hence, ensure balanced crop nutrition. Consequent upon this, this research was initiated to assess the effects of integrated application of ammonium sulphate fertilizer and residues of Gliricidia sepium and Panicum maximum on soil chemical properties and cassava (Manihot esculenta Crantz) performance. The experiment was carried out at the Teaching and Research Farm of the Ekiti State University, Ado – Ekiti, Nigeria, during 2016 and 2017 cropping seasons. The experiment was laid out in a randomized complete block design, with three replicates. The ammonium sulphate fertilizer and plant residues combination treatments included: sole ammonium sulphate fertilizer (SASF); ammonium sulphate (ASF)+Gliricidia sepium residues (GSR) (ASF+GSR); ammonium sulphate fertilizer+ Panicum maximum residues(PMR) (ASF+PMR) and no fertilizer application (NFA) (i.e.check). The results obtained indicated existence of significant (P = 0.05) differences among the different ammonium sulphate fertilizer and plant residues combination treatments as regards their effects on soil chemical properties and cassava root yield. Relative to initial nutrient status of the soil before cropping, at the end of 2016 cropping season, ASF+PMR and ASF+GSR increased soil organic carbon (SOC) by 5 and 15%, respectively, contrasting decreases of 60 and 45% for SAS and NFA, respectively. Similarly, at the end of 2017 cropping season, ASF+PMR and ASF+GSR increased SOC by 12 and 24%, respectively, contrasting decreases of 71 and 60% for SASF and NFA, respectively. At the end of 2016 cropping season, ASF+PMR and ASF+GSR increased total N by 15 and 33%, respectively, contrasting decreases of 30 and 63% for SASF and NFA , respectively. At the end of 2017 cropping season, ASF+PMR and ASF+GSR increased total N by30 and 53%, respectively, contrasting decreases of 43 and 75% for SASF and NFA, respectively. Mean values of cassava root yield data over the two years of experimentation indicated that, integrated application of ammonium sulphate fertilizer and plant residues significantly increased cassava root yield from 3.00 t ha-1 for NFA to 3.89, 8.39 and 8.22 t ha-1 for the respective SASF, ASF+GSR and ASF+PMR.