Pertumbuhan industri makanan masih menjadi salah satu industri yang berkembang dengan pesat di Indonesia. Pada tahun 2011, industri makanan telah mengalami pertumbuhan sebesar 7% dan pada tahun 2012 meningkat menjadi 8%. Di kota metropolis yang didukung dengan peningkatan jumlah populasi yang tinggi dan daya beli masyarakat yang semakin baik, serta perubahan pola makan masyarakat bisnis (middle-up) yang cenderung makan di luar rumah menyebabkan pertumbuhan konsumsi makanan olahan hingga 41% dalam kurun waktu lima tahun terakhir. Penelitian ini ditujukan untuk mengetahui bagaimana pengaruh inovasi produk, harga, word of mouth, dan perluasan merek terhadap keputusan pembelian Richeese Factory Fast Food Di Surabaya. Sampel yang digunakan pada penelitian ini yaitu para pria dan wanita yang pernah mengkonsumsi Richeese Factory Fast Food di Surabaya minimal dua kali dalam kurun waktu dua bulan sejumlah 120 responden dengan teknik pengambilan sample non probability sampling yakni purposive sampling. Penelitian ini menunjukkan bahwa inovasi produk, harga, word of mouth, dan perluasan merek dirasakan secara positif mempengaruhi keputusan pembelian. Kemudian dilakukan analisis terhadap data yang telah didapat dengan data kuantitatif. Analisis kuantitatif mencakup: uji validitas, reabilitas, uji asumsi klasik, analisis regresi berganda, pengujian hipotesis dengan uji t dan uji F, serta analisis koefisien determinasi (R2) Data-data yang telah memenuhi uji validitas, uji reliabilitas dan uji asumsi klasik diolah dengan program SPSS 16.0 (Statistical Package for Social Science) sehingga menghasilkan persamaan regresi sebagai berikut: KP = 0.211IP+0.180PM+0.180WM+0.099HA. Dimana variabel keputusan pembelian (KP), inovasi produk (IP), perluasan merek (PM), word of mouth (WM), Harga (HA). Pengujian hipotesis menggunakan uji t menunjukkan bahwa empat variabel independen inovasi produk, harga, word of mouth, dan perluasan merek berpengaruh positif signifikan terhadap keputusan pembelian. Kemudian melalui uji F dapat diketahui keempat variabel independen dalam menguji variabel dependen keputusan pembelian. Angka Adjusted R Square sebesar 0,151 menunjukkan bahwa 15,1 persen variabel keputusan pembelian dapat dijelaskan oleh keempat variabel independen dalam persamaan regresi. Sedangkan sisanya 84,9 persen dijelaskan oleh variabel lain diluar keempat variabel yang digunakan dalam penelitian ini / The development of food industry still be one of the most rapid growth in Indonesia. In 2011, the food industries has grown up to 7% and in 2012 grow up to 8% . In the metropolitan town that are supported with the rapid growth of population and better purchasing power, as well as the change of business community dietary (middle up) who tend to eat outside led to the growth of processed food consumption by 41% within the last five years. This thesis is addressed to understand how the impact of innovation product, price, word of mouth and brand extension toward purchase decision for Richeese Factory Fast Food in Surabaya. The sample that is being used in this thesis is characterize as for men and women who ever consume Richeese Factory Fast Food in Surabaya with the minimum of purchasing two times within 2 months to 145 respondents using purposive sampling technique. This thesis shows that product innovation, price, word of mouth and brand extention has positive impact toward purchase decision. After that, data analysis is conducted and has obtained with quantitative data. Quantitative analysis includes: validity test, reliability test, classic assumption test, multiple regression analysis, hypothesis test with the t test and F test, and the coefficient of determination (R2). The data that have met the requirement of validity test, reliability test and classic assumption test are processed with the program SPSS 16.0 (Statistical Package for Social Science) resulting regression equation as follows: KP = 0.211IP+0.180PM+0.180WM+0.099HA. which the KP is the variable of purchase decision, IP is the variable of product innovation, PM is the variable of brand extention, WM is the variable of word of mouth and HA is the variable of price. Hypothesis test using t test shows that the four independent variables of innovation product, price, word of mouth and brand extention have positive and significant impact toward purchase decision. Then F can be determined by testing four independent variables in testing the dependent variable purchase decision. The value of Adjusted R Square is 0.151, this indicates that 15.1 percent variable of purchase decision can be explained with the four independent variables within the regression equation. Whereas the remain 84.9 percent can be explained with the other variables outside of the four variables that are used in this thesis