The development of the food and beverage industry in Indonesia is very rapid and currently, people can easily find many cafes in various places. Blue Diamond Cafe Pematangsiantar experienced a decline in the level of customer visits. Based on online reviews, several bad reviews and comments were found about the cafe which had a bad store atmosphere, inadequate facilities, and poor quality of service provided. This research aims to find out whether store atmosphere, facilities, and service quality can have a significant influence on customer purchasing decisions at Blue Diamond Cafe Pematangsiantar. In this research, the author used quantitative research methods. The sample in this study was 140, obtained by distributing questionnaires to people who had purchased products and visited the Blue Diamond Cafe. The data distributed to 30 respondents was tested using validity and reliability tests. Sample collection used non-probability sampling with the convenience sampling method. The results of this study used SPSS 25 to carry out normality tests, heteroscedasticity tests, multicollinearity tests, multiple linear regression tests, coefficient of determination tests, and hypothesis tests. The results of the coefficient of determination show a result of 50.6% that the store atmosphere (X1), facilities (X2), and service quality (X3) influence customer purchasing decisions. Based on the results of the analysis, Blue Diamond Café Pematangsiantar can provide air conditioning, availability of parking space, and also improve the quality of service to guests. / Perkembangan industri makanan dan minuman di Indonesia sangat pesat dan saat ini orang-orang dapat dengan mudah menemukan banyak cafe diberbagai tempat. Blue Diamond Cafe Pematangsiantar mengalami penurunan dalam tingkat kunjungan pelanggan. Berdasarkan ulasan online, ditemukannya beberapa ulasan dan komentar buruk tentang cafe yang memiliki atmosfer toko yang buruk, fasilitas yang kurang memadai dan kualitas pelayanan yang diberikan buruk. Penelitian ini bertujuan untuk mengetahui apakah store atmosphere, facility dan service quality dapat berpengaruh signifikan terhadap keputusan pembelian pelanggan di Blue Diamond Cafe Pematangsiantar. Dalam penelitian ini, penulis menggunakan metode penelitian kuantitatif. Sampel dalam penelitian ini sebanyak 140, diperoleh dengan menyebarkan kuesioner kepada orang yang pernah melakukan pembelian produk dan berkunjung ke Blue Diamond Cafe. Data yang dibagikan kepada 30 responden diuji dengan uji validitas dan reliabilitas. Pengumpulan sample menggunakan non-probability sampling dengan metode convenience sampling. Hasil pada penelitian ini menggunakan SPSS 25 untuk melakukan uji normalitas, uji heteroskedastisitas, uji multikolinearitas, uji regresi linier berganda, uji koefisien determinasi, serta uji hipotesis. Hasil koefisien determinasi menunjukkan hasil sebesar 50.6% bahwa atmosfer toko (