Chlorella vulgaris Alga (C.vulgaris) is a highly nutritious microalgae, Also Lactobacillus reuteri Bacteria (L.reuteri) produce a high amount of phytase enzyme that liberates necessary minerals for health. The present work aimed to study the enhancement effects of C.vulgaris and L.reuteri on the puberty of young rabbit-doe exposed to heat stress (HS). 28 young New Zealand rabbit-does were used and divided into four groups (n=7). (G1) was used as a negative control group. (G2) exposed to heat stress. (G3) & (G4) dietary supplemented with C.vulgaris (60mg) and L.reuteri (count producing 250 phytase units)/rabbit/day for 4 weeks, respectively. The live weight, feed intake, daily gain, and food conversion ratio were recorded. Plasma chemistry was estimated for the liver and kidney function parameters as Albumin, Creatinine, Alanine-Transaminase(ALT), Aspartate-aminotransferase(AST), and the antioxidant markers Catalase and Super Oxide Dismutase(SOD), Also the oxidative stress factor Malondialdehyde(MDA), in addition to the reproductive hormones progesterone(P4), follicle-stimulating-Hormone(FSH), Luteinizing-Hormone(LH), and cytokines Interlukine-1(IL-1), Tumor-Necrosis-Factor α(TNFα), Gamma-Interferon(INFϒ), and Transforming-Growth-Factor-Beta-2(TGFB₂). Tissue samples from ovary, liver, small intestine, and spleen were examined histopathologically. The C.vulgaris and L.reuteri-supplemented groups showed significant up-regulation for the antioxidant markers and reproductive hormones. They also, marked down-regulation for the liver and kidney function enzymes, and oxidative stress factor (MDA). Moreover, a marked increase in growing and mature follicles was found. In conclusion, C.vulgaris and L.reuteri enhanced the rabbit puberty and ameliorated the adverse heat stress effects by promoting the growth rate, oxidative status, and ovarian follicular activity.