| 25 expired proprietary (ex-PVP) U.S. maize inbred lines were crossed to two elite tester inbred lines CA193 and CA749 by NCII genetic design. These crosses and two hybrid checks Jidan27 and Xianyu335 were evaluated for main agronomic traits in Gong zhuling of Jilin province and Harbin of Heilongjiang province to analyze the breeding potential of 25 ex-PVP U.S. inbred lines. The results showed that 13 inbred lines, including 2MCDB, LH198, PHR63, LH184, PHHH9, MBWZ, PHJR5, LH186, PHT47, LH217, PHMK0, PHEG9 and LH218, had high general combining abilities (GCA) effects for grain yield. Four of the 13 elite lines, 2MCDB, LH184, LH186, PHJR5 and PHT47, also showed the potential of reducing moisture content in harvest time. The inbred line PHT47 and PHJR5 had the best breeding potential for increasing ear row number and shortening growth period in the study. The two cross, CA193×PHT47 and CA749×2MCDB, could be used to develop new lines targeting to the two lines CA193 and CA749, since they showed moderate yield and more row number per ear. The three high-yielding crosses comparing to Jidan27 hybrid, CA193×PHT47, CA193×2MCDB and CA193×PHJR5, could be tested to develop new hybrids.