Second-party punishment (SPP) and third-party punishment (TPP) are essential in regulating social behavior and maintaining social norms; however, their effectiveness may wane when punishment is delayed. Furthermore, the decision-making and neural mechanisms underlying SPP and TPP under temporal delays remain largely unexplored. This study investigated these processes using a hypothetical criminal scenario assessment task with fMRI. Results showed increased activity in the bilateral precuneus and left temporoparietal junction (TPJ) in SPP compared to TPP. Interestingly, third parties imposed more severe punishment in delayed conditions than in immediate ones, accompanied by enhanced neural activity in the left dorsomedial prefrontal cortex (dmPFC), left TPJ, left ventrolateral prefrontal cortex (vlPFC), right ventromedial prefrontal cortex (vmPFC), and right caudate nucleus. In contrast, SPP showed no significant changes in punishment or neural response across immediate and delayed conditions. Multivariate pattern analysis further indicated that left dmPFC, left TPJ, left vlPFC, right vmPFC, and right caudate function together to encode punishment severity in TPP contexts. Collectively, these findings illuminate the neurocognitive mechanisms underlying delayed punitive decision-making in both SPP and TPP contexts, with implications for understanding justice-related processing in the human brain under time constraints.