Many firms are often faced with drastic price fluctuations and uncertain demand consumptions when procuring raw materials. Therefore, it has become increasingly important for the firms to study the optimal procurement problem under uncertain price and uncertain demand. Most of the previous studies have focused on the procurement optimization problem with single-parameter uncertainty, and dominantly assume that the parameter fluctuated randomly, but in reality the price and demand are often uncertain simultaneously and cannot be observed randomly. Based on the online theory, this paper studies the online procurement problem of raw materials with uncertain price and demand, we construct the corresponding mathematical model, and a dynamic effective competitive strategy is then analyzed. Finally, the competitive ratio performance for the proposed strategy is derived and the numerical analysis further shows that the strategy achieves an even better empirical performance.