The aim of this study was to investigate the effect of different levels of drought stress on morphological traits of Capparis spinosa L. and to investigate the effect of biochar on increasing the plant tolerance to drought stress. This experiment was conducted as a factorial experiment in a completely randomized design with three replications in the greenhouse of the Faculty of Natural Resources, Yazd University. The experimental factors included drought stress at four levels (100, 75, 50 and 25% of field capacity), biochar at three levels (0, 1 and 2% by weight). After 10 months of drought treatment, samples were collected to measure the number of leaves, number of lateral branches, relative leaf water content, stem length, maximum root length, root volume, fresh weight of shoots and roots, dry weight of shoots and roots. The results showd that the highest number of leaves (112% increase compared to the control) and stem length (51% increase compared to the control) were observed in the treatment of 75% of the field capacity with 1% biochar, the highest fresh weight (255% increase compared to the control) and dry weight of the shoot (348% increase compared to the control) were observed in 75% of the field capacity with 2% biochar, as well as the highest fresh weight (70% increase compared to the control) and dry weight of the root (54% increase compared to the control) and the volume of the taproot (67% increase compared to the control) were observed in 25% of the field capacity with 1% biochar, and the highest taproot length (37% increase compared to the control) was observed in the 75% field capacity and without biochar.