Field experiments were conducted during two successive growing seasons ( 2017/2018 and 2018/2019) in Guava orchard at Kafr Al Dawar district, Beheira Governorate, Egypt, to investigate the effect of water regime levels: 100% (E1), 80% (E2) and 60% (E3) of crop evapotranspiration (ETc) under two irrigation systems: furrow irrigation (I1) and surface drip irrigation (I2) on water use efficiency, growth parameters, yield components, and economic analysis of four years old guava trees grown in clay soil. The field experiments were implemented in arandomized complete block design with three replicates. The obtained results indicated that the highest shoot length, number of leaves/m and leaf area were obtained due to T2E1 treatment (drip irrigation with 100% ETc), followed by I2E2 treatment (drip irrigation with 80 % ETc). The average highest guava yield of the two growing seasons was 26.64 tons/ha which was obtained as a result of I2E1 treatment (drip irrigation with 100% of ETc). The lowest guava yield (20.24 and 17.90 tons/ha) were obtained due to I1E3 treatment (furrow irrigation with 60% of ETc) for the two growing seasons, respectively. Yield components such as number of fruits/m, length of fruit (cm), diameter of fruit (cm) , fruit size (cm3) , fruit weight (gm.) and yield (kg/tree) were significantly effected (P˂ 0.05) by water regime levels and irrigation systems. Water use efficiency (WUE) of drip-irrigated treatments was higher than that obtained from furrow irrigated treatments in the two growing seasons. WUE increased from 2.37 to 3.34 kg.m-3 for drip - irrigated treatment, and from 1.63 to 2.18 kg.m-3 for furrow -irrigated treatments. Fruit quality such as TSS (%), acidity (%) and TSS / Acidity ratio were not significantly affected by irrigation systems and water regime. For the economical results, the maximum value of net return was due to I2E1(24411 LE/fed)treatment for the two growing seasons and the minimum value of total return was the result of T1E3 (6344 LE/fed)treatment for the two growing seasons. The maximum values of water productivity were obtained under T2E1 (5.56 LE/m3) and I2E2 (5.25 LE/m3) treatments in the two growing seasons.