The aim of diploma thesis is a comparison of flame and fusion laser cutting of thin metal sheets for ACO Industries k. s. company, where the experimental part was also realized. After consultation with company, the thesis was extended by data samples, which were cut by compressed air for comparison with other two gases. The optimization design of cutting parameters was created by Taguchi method. Afterwards the surface roughness of samples was measured. Based on Ra and Rz5 parameters, the samples were classified to classes based on their accuracy according to ISO 9013 standard. According to results the fusion method of laser cutting is more suitable method, especially for its good quality of cutting edge, which is not affected by the oxidic ...