Lead is one of humans and animals' most common and hazardous heavy metals. This study aimed to investigate the effect of white guava (Psidium guajava) fruit juice on the seminiferous tubule diameter and epithelium thickness in rats (Rattus norvegicus) exposed to lead acetate. The research design was a completely randomized design (CRD). A total of 25 male rats with an average weight of 200 grams were used for the study, divided into 5 treatment groups, each consisting of 5 rats. The treatments were as follows: the control group (C) was given distilled water orally; the T0 group was induced with lead acetate (50 mg/Kg BW) orally; the T1, T2, T3 groups were induced with lead acetate (50 mg/Kg BW) and then given 25%, 50%, and 100% concentration of white guava fruit juice, respectively. All the treatments were conducted for 14 days. The histopathology slides of the testis were made with HE staining, and the seminiferous tubule diameter and epithelium thickness were measured. The data were analyzed using One Way ANOVA and Duncan test (p<0.05). The results showed that the control group (C) which was given distilled water only had a seminiferous tubule diameter and epithelium thickness of 336.24±23.32 µm and 66.46±4.39 µm, respectively. The T0 group which was induced with lead acetate only showed a reduction in the diameter and epithelium thickness of seminiferous tubules (243.38±49.35 µm and 44.08±14.45 µm). The members of the T1, T2 and T3 groups showed positive effects on the diameter (323.49±22.82 µm; 314.41±13.04 µm; 325.04±16.88 µm, respectively) and epithelium thickness (56.36±3.36 µm; 60.50±3.81 µm; 66.744±9.50 µm, respectively). There was no significant difference reported between each group. The administration of guava juice to rats induced with lead acetate can positively affect the diameter and epithelium thickness of seminiferous tubules.