The purpose of this study is to investigate the effect of audit quality , Board characteristics and environmental uncertainty  on the  Tax Avoidance activities, and further provide empirical evidence in Egypt of tax avoidance practices in firms listed on the Egyptian Stock Exchange                          .                                                                                              In order to achieve the study objectives, Its examined the effect of  audit quality  by(audit office  size , audit fees , audit tenure) , the board characteristics  by( board size , board independence, CEO duality) and the environmental uncertainty on tax avoidance activities through the measure of the Current ETR . This study was applied on a sample of 30 Egyptian firms listed at the Egyptian stock Exchange during the period 2019-2022, Multiple regression analysis was used to ascertain the relationship between the independent variables and the dependent variable                                    .    The results of the study , indicate  the negative effect of  audit quality  by( the audit office size and audit fees) on the tax avoidance activities when measured through Current ETR, while audit tenure  has positive effects on tax avoidance activities  , Also, there is negative  effect of the board characteristics  by( board size and board independence) on the tax avoidance activities ,while CEO duality has positive effects on tax avoidance activities  , besides positive effects of environmental uncertainty on tax avoidance activities and negative effect of the managerial ability on tax avoidance activities                                                                                                                         . Depending on this: the study has recommended the necessity of studying all the variables that have an  effect on tax avoidance practice in Egyptian firms to reduce tax avoidance activities , to avoid its harmful impact on the state and society