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The potentiality of using citric acid modified kola nut pod to remove selected heavy metals (Lead (II), Cobalt (II) and Cadmium (II) ions from aqueous solution was investigated. The batch adsorption experiments were conducted to investigate the effect of variable conditions such as pH, contact time, temperature, initial metal concentration and adsorbent dose. There was an increase in the percentage removal of heavy metal ions as the pH increases with the optimum value 99.25% at pH 7 for Pb (II), 95.79% for Co (II) at pH 7 and 99.38% for Cd (II) at pH6.The optimum value of percentage removal for Pb (II), Co(II) and Cd(II) at contact time 60 min, 120 min and 120 min were 98.40%, 97.72% and 98.90% respectively. Also, the optimum value for initial metal concentration for Pb (II) was 91.30%, Co (II) (95.21%) and Cd (II) (95.86%) at 25mg/L. The optimum value of Pb (II), Co (II) and Cd (II) at 2.0g dose was 98.13%, 95.21% and 957.83% respectively. Kinetics parameters obtained showed that the kinetic data did not obey the pseudo-first order. The Pseudo-second order was obeyed throughout the adsorption process for the removal of metals. The linearized Isotherm models (Langmuir, Freudlich and Temkin isotherm) were employed to explain the equilibrium data. The results revealed that the removal of heavy metals by citric acid modified kola nut pod adsorbent fitted well into Freundlich model. The n values and KF values for the selected heavy metals used were favourable. However, the H o for Pb(II), Co(II) and Cd(II) ions removal process was negative using citric acid modified kola nut pod adsorbent. This implies that the adsorption process was exothermic. Also, the So values were all positive suggesting that there were some degree of randomness by the metal ions with increase in temperature. The Go values at 298k, 313k, 328k, 343k and 358k were all negatives indicating that the reaction was spontaneous. The adsorbent prepared in this study can be used for treatment of wastewater contaminated with heavy metals. Keywords: Adsorption, Citric acid modified adsorbent, modification, Cola acuminata, pseudo second order, Freundlich