Forty-four maize inbred lines, which were from different heterotic groups with known levels of ear rot resistance, were tested for resistance to ear rot by artificial inoculation using Fusarium verticilloides or Fusarium graminearum in 2016 and 2017. As observed, the inbreds lines from Tangsipingtou group showed overall susceptible, while the inbred lines from Lvdahonggu group showed overall resistant to ear rot. Within the Raid group, different inbred lines represented the variation of resistance. The inbred lines Ji V203, Cheng 351 and Dan 598 showed simultaneously highly resistant against infections of Fusarium verticilloides and Fusarium graminearum, while PHTD5 and Ye 81162 were highly susceptible. We also observed the differences on levels of resistance of 44 inbred lines in two calendar years, suggesting that the incidence of corn ear rot was greatly affected by environmental factors. That also provided an explanation on the complexity of resistance to ear rot. Notably, the resistant phenotype in highly-resistant and highly-susceptible inbred lines were reproducible over years, while inbred lines with moderate resistance were largely influenced , likely associated to the environmental factors. Taken together, these results provided insight in genetic improvement of resistance to ear rot in maize.