The experiment aimedto determine the protein digestibility and milk protein of lactating dairy cowsfed at forage and concentrate ratio.The materials used were 12 dairy cows at II and III month lactating period. The experiment was done by Completely Randomized Designs (CRD) for 3 treatments and 4 replications. The treatments applied were proportion of forage and concentrate in the rations, namely 50:50 (T0), 55:45(T1), and 60:40 (T2), respectively.The parameters observed were protein digestibility, milk protein, dry matter intake (DMI) and crude protein intake (CPI).The results showedthat protein digestibility ofT0; T1; and T2 were66.26; 62.03; 67.48%, while milk protein were 247.08; 270.70; 287.79 g/head/day, respectively. The DMI ofT0; T1; and T2 were15.16; 15.37; and 16.30 kg/head/day, while CPI were1.75; 1.74; and 1.81kg/head/day, respectively. All of those parameterswere not significantlydifferent (P>0.05).Therefore it could be concluded that ratio of forage and concentrates in the ration forlactating dairy cow did not affectfeed protein digestibility and milk protein.