Latar Belakang: Bayi sangat prematur adalah kelompok bayi risiko tinggi yang rentan terhadap luaran neurodevelopmental yang buruk. Penelitian menunjukkan bahwa pemberian nutrisi secara dini dan agresif dapat mengurangi kejadian malnutrisi pada bayi sangat prematur. Saat ini, RSUP Fatmawati belum mempunyai protokol nutrisi yang standar untuk bayi prematurnya dan ingin melakukan perubahan dengan menerapkan protokol standar nutrisi bayi prematur dari RSCM. Tujuan: Untuk mengetahui beda waktu kembali ke berat lahir dan pola pemberian nutrisi bayi sangat prematur/BBLSR yang lahir dan dirawat di Unit Neonatologi RSUP Fatmawati sebelum dan sesudah penerapan protokol standar nutrisi bayi prematur RSCM. Metode: Dilakukan penelitian quasi eksperimental terhadap 23 bayi sangat prematur/berat lahir sangat rendah di Unit Neonatologi RSUP Fatmawati pada bulan Juli – November 2019. Bayi dieksklusi bila orangtua menolak berpartisipasi atau mempunyai kelainan kongenital yang mempengaruhi status nutrisi. Sampel pada kelompok intervensi diberikan nutrisi sesuai protokol standar nutrisi bayi prematur RSCM dan diikuti hingga kembali ke berat lahir dan mencapai fullfeed. Pola pemberian nutrisi yang juga dievaluasi sebagai luaran sekunder (waktu dimulainya nutrisi enteral dan mencapai fullfeed, waktu dimulainya pemberian protein dan lipid, waktu tercapainya protein, lipid dan kalori tertinggi serta jumlah protein, lipid, kalori dan GIR tertinggi). Data pasien pada kelompok kontrol diambil dari data rekam medik bayi sangat prematur/berat lahir sangat rendah yang sudah pulang dari RSUP Fatmawati dari Januari 2016 – Juni 2019 dan dibandingkan dengan kelompok intervensi. Hasil: Penerapan protokol standar nutrisi bayi prematur RSCM dapat mempercepat waktu kembali ke berat lahir (kontrol vs intervensi: 16,7 (5,1) vs 7,4(3,5) hari, p= 0,00) dan mempercepat growth velocity (kontrol vs intervention: 8,9 (6,9) vs 14,6 (6,0), p=0,002) pada bayi sangat prematur/BBLSR yang dirawat di Unit Neonatologi di RSUP Fatmawati. Kesimpulan: Penerapan protokol standar nutrisi bayi prematur RSCM dapat mempercepat waktu kembali ke berat lahir dan growth velocity pada bayi sangat prematur/BBLSR yang dirawat di Unit Neonatologi RSUP Fatmawati. Kata kunci: nutrisi bayi prematur, nutrisi agresif dini, waktu kembali ke berat lahir, growth velocity......Background: Very premature infants are a group of high-risk infants who are vulnerable to poor neurodevelopmental outcomes. Research shows that early and aggressive nutrition can reduce the incidence of malnutrition in very premature infants. At present, Fatmawati Hospital does not yet have a standard nutritional protocol for premature infants and want to make changes by implementing a standard protocol for preterm infant nutrition from RSCM. Objective: To determine the difference in days to regain birth weight and the pattern of nutrition for very premature/very low birth weight infants who were born and hospitalized in the Neonatology Unit of RSUP Fatmawati before and after the application of the standard protocol of premature infant nutrition of RSCM. Methods: A quasi-experimental study of 23 very preterm/very low birth weight infants in the Neonatology Unit of Fatmawati Hospital from July to November 2019. Infants were excluded if parents refused to participate or had congenital abnormalities that affects nutritional status. Samples in the intervention group were given nutrition according to RSCM premature infant nutrition protocol and followed until they return to birth weight and achieve fullfeed. Nutritional patterns were also evaluated as secondary outcome (day to begin enteral nutrition, growth velocity, days to reach fullfeed, days to start protein and lipid, days to reach the highest protein, lipid and calorie intake and the highest amount of protein, lipid, calories and GIR given). Data of samples in the control group were taken from medical records of very premature/very low birth weight babies discharged from Fatmawati Hospital from January 2016 - June 2019 and compared with the intervention group. Results: The application of RSCM premature infant nutrition protocol can shorten the days to regain birth weight (control vs intervention: 16.73 vs 7.43 days, p = 0.00) and fasten growth velocity (control vs intervention: 8,9 (6,9) vs 14,6(6,0), p=0,002) in very premature/low birth weight infant who were treated in the Neonatology Unit of Fatmawati. Conclusion: The application of RSCM premature infant nutrition standard protocol can accelerate time to regain birth weight and growth velocity in very premature/low birth weight infant in the Neonatology Unit, Fatmawati Hospital.