In vitro grown plant materials of jojoba plant (Simmondsia chinensis L.) were used to study the effect of medium strength and activated charcoal (AC) on shoot multiplication and growth. Reduction in shoot multiplication was detected when explants were cultured on half strength MS medium. The highest shoot multiplication was obtained on the full strength MS medium containing 3.0 mg/l BAP and 0.1 mg/l NAA. Increase the osmotic pressure of the medium by increasing the concentrations up to double strength MS medium resulted in an increase of the growth parameters. Jojoba multiplication and in vitro growth was improved using activated charcoal; the best results were obtained on MS medium supplemented with 1 gm/l activated charcoal, 3 mg/l BAP and 0.1 mg/l NAA. While gene expression was stable under the influence of activated charcoal, it expressed some variation under the influence of medium strength. On the other hand, full medium strength resulted in maximum shoot multiplication and expressed several polypeptides with different molecular weights (150, 102.6, 65 and 42 KDa) and new peroxidase isoform (POX-1). Double strength MS medium expressed one polypeptide (8.6 KDa). Increased staining intensity of peroxidases and stimulate shoot growth.