Twelve lactating Friesian cows at the peak of lactation curve and in their first to fourth parity were used to study the effect of  feeding diets containing different levels of apple pomace silage on their productive  performance.  By using complete switch- back design, animals were randomly divided into four similar groups according to body weight, milk yield and number of  lactations ( 3 cows in each). Cows in the first group were fed a control ration (R1) which consisted of 50% concentrate feed mixture (CFM), 40%,  berseem (Trifolium alexandrinum) (B) and 10% rice straw (RS). Groups R2, R3 and R4 were fed the same formula of control with replacing 25, 35 and 40% of berseem by apple pomace silage (APS) , respectively. Results indicated that contents of CP and ash were low, while contents of  CF, EE and NFE were high in apple pomace silage. Cows  fed the 25% APS-ration (R2) recorded significantly (P<0.05) the highest digestibility coefficients for ( DM, OM, CP, CF, EE and NFE) and subsequently the highest TDN value, while control ration (R1) showed significantly the highest value of DCP. Slight change regarding rumen liquor parameters, in particular pH and TVFA's concentrations, due to dietary treatments were found. Concentration of NH3-N in rumen liquor was significantly (P<0.05) the highest with cows fed R1(control ration). Concerning milk production, significantly the highest actual daily milk and 4% FCM yields were recorded with R2, while the lowest corresponding values were of R4 and the values of  R1 and R2 were in the middle. Also, the superiority of milk composition as percentages of fat, protein, total solids (TS) and solids non fat (SNF) were associated with the low APS-ration (R2). The same rations had significantly the best value related to the feed efficiency trait, while the worse values were almost   those of R1 and R4 rations. Economically, results also indicated that R2 had the favorably added value, while R4 appeared to be the least one. So, it was concluded that apple pomace silage can be efficiently substitute 25% of berseem in diets of dairy cows during winter season.