Small companies find it difficult to implement production management systems. This causes problems of overproduction, high inventory and high rates of defective products. Lean Manufacturing acts as a methodology to achieve waste elimination. It is important that companies identify their current level of Lean to improve their operations. This work aims to present a model using fuzzy logic, applied in a small metallurgical industry. A Fuzzy inference model was specified and modeled on the software fuzzy toolbox MATLAB R2013a®. The simulation performed on the model took into account the current reality of the company, noting that there are no Lean metrics in its processes. A great advantage of the model is the possibility of adjustments for any type of organization since the input and output variables can receive other linguistic values.