Adsorption of Reactive Yellow 145 (RY145) and Remazol Black RL (RBRL) onto pine needles (PN) was investigated with respect to initial dye concentrations, adsorbent dosage, and pH in a batch manner. The obtained data in the study were described according to the Langmuir and Freundlich isotherm models and the Langmuir model describes the experimental data very well with a q^sub max^ value of 13.831 and 7.225 for RBRL and RY145 respectively. As the pH decreased, adsorption density increased gradually and the highest adsorption density was obtained at pH 2 for both adsorbents (91.57 and 64.77% for RBRL and RY145 respectively). Equilibrium adsorption rates of 70.15% with RY145 and 86.72% with RBRL onto PN were observed at 90 min. In order to better model the kinetics of adsorption, first order, pseudo second order and second order models were applied. Among these models, the pseudo-second order kinetic model provided a good correlation for the adsorption of RY145 and RBRL by PN with a R^sup 2^> 0.999. Results showed that pine needles have great potential to remove Reactive Yellow 145 (RY145) and Remazol Black RL from aqueous solutions. dely used and effective adsorbent found in the literature is activated carbon, but its use is limited by the high costs associated with its regeneration or replacement [13, 17]. According to Bailey et al., an adsorbent can be considered as low-cost if it requires only a small process to prepare, is abundant in nature, or is a by-product or waste material from another industry [17]. Certain waste products from industrial and agricultural operations, natural materials and biosorbents represent potentially economical alternative adsorbents [18]. In the literature many similar agricultural adsorbents could be found. Ucar and Armagan (2012) used cotton seed shell to remove Reactive Black 5 from aqueous solutions and maximum adsorption density was obtained as 12.19 mg.g-1 in the conditions of pH 2 and the contact time of 30 min [19]. In another adsorption study, where dehydrated beet pulp carbon and Chemazol Reactive Red 195were used, maximum adsorption capacity was obtained as 58.0 mg.g-1 at temperature of 50 °C. Similar to Ucar and Armagan's study, maximum adsorption density was again obtained in low pH (pH 1) [20]. Agricultural wastes can also be used to produce activated carbon. Cardoso et al. (2011) used Brazilian pine fruit shells to produce activated carbon and compared its adsorption efficiency with the natural form of pine shells. As activated carbon is an effective material, authors also reported favorable adsorption rates at pH values ranging from 2.0 - 7.0, whereas this value is 2.0 - 2.5 for natural form of pine shells. Contact time also varied between two materials (4 and 14 hours for activated carbon and natural form of pine shells respectively) [21]. Although processing Brazilian pine fruit shells to form activated carbon may be costly, it exhibits a great advantage in application. Different from agricultural originated adsorbents, methyl violet is successfully removed from aqueous solutions by adsorption onto halloysite nanotubes. The clay minerals of halloysite nanotubes exhibited rapid adsorption rate and high adsorption capacity of 113.64 mg.g-1. Pseudo second order kinetic model is well fitted to kinetic experiment results with correlation coefficients greater than 0.999 [22]. Other than the studies summarized above, many workers have employed different materials such as perlite [23], biomaterial [24], recycled alum sludge [25], zeolites [26], agriculture waste residues [27] for removing the dyes from wastewater. For more studies upon the adsorption of textile dyes by low cost adsorbents, see the review of Crini [18]. sorption kinetic curve was studied at a dye concentration of 50 mg.L-1. Pseudo first order, pseudo second order and second order models, which control the process, were tested in order to evaluate the kinetic mechanism. As shown in Fig. 2, the time necessary to reach this equilibrium is about 90 minutes. Such a rapid uptake of RY145 and RBRL may indicate that the PN have an affinity for the dyes pointing towards physical adsorption where electrons did not exchange between adsorbent and adsorbate. In addition, desorption studies were performed to explain the interaction of dyes on PN. To do this, 1 g RY145 - PN and RBRL - PN combinations (obtained from the reaction of 1 g PN with 100 mg.L-1 RY145 and RBRL) was added to distilled water and shaken for 90 minutes. At the end of the experiment, in the supernatant, 17.30 mg.L-1 RY145 and 14.28 mg.L-1 RBRL were measured. This experiment shows that interactions between PN and dyes were relatively weak, and therefore likely to be physical. s study, the ability of PN to bind RY145 and RBRL was investigated by means of optimum pH, adsorbent dosage, kinetics and equilibrium. The results indicated that the adsorption process is pH dependent and that maximum adsorption density is obtained at pH 2 for both dyes. The kinetics of RY145 and RBRL adsorption onto PN was studied using the pseudo-first and pseudo-second order and second order kinetic models. The results indicated that the pseudo-second order equation provided the best correlation for the adsorption data. According to pseudo second order model, equilibrium adsorption densities were 2.012 and 6.075 mg.g-1. Optimum contact time was 90 minutes for both dyes. In the adsorption equilibrium studies, the Langmuir equation was used to fit the experimental data obtained. According to experimental data, the Langmuir model provided the 7.225 and 13.831 mg.g-1 maximum adsorption density for RY145 and RBRL, respectively. It is also reported that the percentage removal of RY145 and RBRL increased with increasing PN amount. However, the optimum adsorbent concentration obtained was 2.22 g.L-1. It may be concluded that PN, a free and abundant natural resource, are an efficient adsorbent for the removal of RY145 and RBRL from aqueous solution.