The adsorption kinetics of nickel (II) in aqueous solution with activated carbon from coconut shell was studied by measuring the nickel concentration in the solution (C) as a function of time (t). The parameters studied in this study were adsorption temperature (T), particle diameter of activated carbon (d), and mass ratio of activated carbon to aqueous solution (r). It was found that the adsorption rate increased with the increase of the adsorption temperature and the mass ratio of activated carbon to aqueous solution. On the contrary, it was found that the rate of adsorption decreased with increasing the particle diameter of the activated carbon. Keywords: adsorption kinetic, nickel (II), activated carbon, coconut shell Kinetika adsorpsi larutan nikel (II) dalam air dengan karbon aktif tempurung kelapa dianalisis dengan mengukur konsentrasi nikel pada larutan sebagai fungsi waktu. Parameter yang digunakan pada penelitian ini adalah suhu adsorpsi (T), diameter partikel karbon aktif tempurung kelapa (d), dan rasio massa karbon aktif tempurung kelapa dengan larutan nikel (II) dalam air (r). Hasil penelitian menunjukkan bahwa laju adsorpsi meningkat dengan bertambahnya suhu adsorpsi dan rasio massa karbon aktif tempurung kelapa dengan larutan. Sedangkan, laju adsorpsi menurun dengan bertambahnya ukuran diameter partikel karbon aktif tempurung kelapa. Kata kunci: kinetika adsorpsi, nikel (II), karbon aktif, tempurung kelapa