The purpose of this study was to develop a gas sensor array to estimate the manure nutrient contents. Three metal-oxide gas sensors including methane, ammonia and hydrogen sulfide were used. Forty manure samples were collected from four beef operations in Southwest North Dakota. Manure samples were sent to be analyzed for moisture content, total-nitrogen (Total-N), phosphorus (P), potassium (K) and ammonium-nitrogen (NH4-N). Regression equations were developed showing the relationships between sensor array readings and the lab results. The sensor array was able to estimate manure N, P, and K with correlation coefficients of 0.80, 0.76 and 0.70, respectively.