Cigarette smoke contains three main toxins of carbon monoxide (CO), nicotine, and tar which can cause an increase of Reactive Oxygen Species (ROS) as well as a decrease of antioxidant reserves. The decreasing amount of antioxidant reserves can lead to the damaging of testicular cells, which is known to cause inhibition of cell division of germinal testicular cells. Hence, the production of testosterone hormones is inhibited as well therefore affecting the quality of spermatogenesis. Red dragon fruit juice serves as a possible antioxidant that can avert the ROS, thus preventing the damage of testicular cells. This research is an experiment of “post-test only control group design”. Twenty-five lab rats were given exposure based on their groups, which are KP, KN (positive and negative control respectfully), P1, P2, P3 (exposure 15 minutes + dragon fruit juice with doses 1.44 cc, 2.88 cc, and 4.32 cc respectfully) for 24 days. On the 32^nd day, the concentration of serum testosterone was determined using ELISA. On the same day as well, the amount and the morphology of spermatozoa were determined using a digital microscope. The one-way ANOVA method was used as data analysis with the level of significance p<0.05. Results obtained from this research are summarized as the following. The average concentration of serum testosterone KN 2.29 ng/ml, KP 2.65 ng/ml, P1 2.35 ng/ml, P2 2.86 ng/ml, P3 2.39 ng/ml. The amount of spermatozoa KN 399 million/ml, KP 269 million/ml, P1 312 million/ml, P2 357 million/ml, P3 362 million/ml. The morphology of spermatozoa KN 72.01%, P1 81.09%, P2 82.33%, P3 87.70%. Statistical analysis using one-way ANOVA method shows that the concentration of serum testosterone (p=0.109), the amount of spermatozoa (p=0.005), and the morphology of spermatozoa (p=0.005). Based on the statistical analysis, red dragon fruit juice did not affect the serum testosterone hormone concentration. However, red dragon fruit juice did affect the quality of a cigarette smoke exposed spermatozoa, in which there was an increase in both amount and morphology of spermatozoa.