Abaca banana fiber (Musa textilis) is a source of non-wood fiber that can be used as material in the manufacture of pulp. Oxygen delignification is a process to reduce lignin content in pulp with Kappa numbers as parameters. In addition, carbohydrate degradation also occurs which is indicated by the value of viscosity. The purpose of this study is to predict the decrease in Kappa number, to predict carbohydrate degradation, and to determine the best operating condition based on prediction data obtained from the kinetic reaction model. Comparison between experimental data and prediction data was also analyzed. The prediction of Kappa number was started by developing kinetic model of oxygen delignification from experimental data, in which the rate of Kappa number reduction is dependent to temperature, hydroxy ion concentration, and oxygen pressure with specific reaction order of each species. Similar steps were done for predicting carbohydrate degradation. Prediction of Kappa number and carbohydrate degradation was done at various operating conditions, which are: oxygen pressures (2–5 bar), temperatures (70–100 oC), sodium hydroxide concentrations (NaOH) (1–5%), and heating times (0–120 min). The prediction results showed that the best operating conditions were at pressure of 2 bar, temperature of 85°C, 1% of NaOH for 56.6 min with a viscosity of 878.52 ml/g. This study also performed that the experimental data were fitted well with the prediction data.