Heterosis and inbreeding depression are fundamental genetic phenomena in plant breeding, offering insight into hybrid vigor and the effects of gene fixation on yield and related traits. Maize (Zea mays L.), being a highly heterozygous and cross-pollinated crop, exhibits significant heterosis, making it a prime candidate for hybrid breeding. This article explores the genetic basis of heterosis, evaluates inbreeding depression in maize, and discusses their implications for improving yield and agronomic traits. The findings suggest that judicious use of heterosis and mitigation of inbreeding depression are essential for developing superior maize hybrids and sustaining global food security.