Background: Indonesia is still faced with the problem of malnutrition, one of which is stunting in children. It is reported that in 2021 the prevalence of stunting in East Java has decreased to 23.5% from 26.86% in 2019. One of the causes of stunting is poor parenting practices. The facts show that 2 out of 3 children aged 6-24 months do not get MP-ASI. The purpose of this study was to analyze the effect of modified koya nate (tuna and tempeh) to increase the nutritional value and organoleptic quality as a complement to MPASI to meet protein needs in toddlers. Materials and Methods: The research object for stage 1 is koya which is made from processed tuna and tempeh. The design of this study uses the Research and Development (R&D) method, to find formulas and find out processing techniques that are suitable for the development of processed menus and public acceptance. The research steps consist of the following stages: 1) Define, which is looking for a recipe for making koya from processed tuna and tempeh; 2) Design is the stage of designing a recipe for product development with the percentage ratio of ingredients for tuna; tempe is FR 1 100%; 0, FR2 80%; 20%, FR3 70%; 30%, FR 4 60%; 40%; 3) Develop is the stage of conducting laboratory tests; 4) Dissemination is the researcher providing product samples to be tasted. The panelists used were mothers of toddlers as many as 30 people. Results: Kandungan protein pada koya Nate antara 21, 83 gr % sampai 26, 72 gr %. Kandungan lemak pada koya Nate antara 15, 4 gr% sampai 28, 11 gr%. Kadar air pada koya Nate dari 4, 60 % sampai 8, 21 %. Kenaikan tertinggi, yaitu hampir sebesar 50 % terdapat pada koya Nate komposisi ikan 100 % serta komposisi ikan 80 % dan tempe 20%. karakteristik rasa, tertinggi penilaian tingkat “sangat suka” adalah pada Nate dengan komposisi 80% : 20%. Hasil statistik uji T2 sampel bebas didapakan perbedaan nilai proximat antara bahan atau adonan Nate dengan koya Nate yang sudah dalam bentuk bubuk, masing-masing pada p = 0,001, 0,005, 0,000 dan 0,002. Hasil statistik uji ANOVA menunjukkan ada perbedaan yang significant kandungan protein pada 4 formula koya Nate (p = 0,000). Demikian pula dengan kandungan lemak, uji statistik menunjukkan perbedaan yang significant koya Nate dengan 4 formula (p = 0,003). Kandungan kadar air dan kadar abu antar formula juga berbeda secara significant, masing-masing dengan p = 0,000 untuk kadar air dan p = 0,002 untuk kadar abu. Hasil analisis Penentuan Koya Nate terbaik diperoleh jumlah skor tertinggi adalah pada Formula 80 %: 20 %. Pendugaan umur simpan pada koya Nate terbaik yaitu formula 80 %: 20 %. Conclusion: Koya Nate, which is a processed menu made from tuna and tempeh, is quite easy to make. It has been proven to increase the protein value per 100 grams compared to when it is still in dough form, or like ordinary dishes that are not made in powder form. The Koya Nate formula with added tempeh has a higher fat content than that without added tempeh. The shelf life of Koya Nate can be up to 2 months. The form is in the form of powder (koya) and contains protein from fish and tempeh, as well as the use of coconut milk in its manufacture can provide good nutritional value and support as an additional PMT ingredient for preventing stunting toddlers.