Energy values of maize silages harvested and ensiled at before silking (BS), silking (S), milk line (ML) and half milk line (HML) were determined by nylon bag and enzyme (pepsin-cellulase) methods. In the nylon bag technique, dry matter (DMD) and organic matter digestibility (OMD) of maize silages (60.02 and 65.63% BS stage) were reduced by advancing maturity stage. In the enzyme method, when DMD of maize silages (55.24% at BS stage) was reduced, OMD (42.20%) was increased by advancing maturity stage (P<0.05). Determined DMD and OMD values with nylon bag technique as well as digestible (DE), metabolizable (ME) and net energy for lactation (NEl) method were higher than the enzyme method (P<0.01). According to the linear regression analysis, relationships between two methods were nonsignificant. But the results of 2(nd) degree polynomial function regression analyses, all relationships were significant and the highest R-2 value was 0.63 for following equation: Nylon bag organic matter digestibility=62.79-22.99STAGE+0.014EME+3.99STAGE(2)-0.0001EME(2). Thus enzyme method could be used only at milk line for estimations of DMD, OMD, DE, ME and NE1.