In this research, results of an experimental interaction effect of operating parameters on tensile strength carbon fibers from a commercial PAN-based precursor are investigated. Ten parameters at two and four levels ($L_{32}=2^1{ imes}4^9$) were investigated: stabilization temperature at first stage (STFIS), stabilization duration time at first stage (SDTFIS), stabilization temperature at second stage (STSS), stabilization duration time at second stage (SDTSS), stabilization temperature at third stage (STTS), stabilization duration time at third stage (SDTTS), stabilization temperature at fourth stage (STFOS), stabilization duration time at fourth stage (SDTFOS), carbonization temperature (CT), and carbonization duration time (CDT). In this study, Taguchi method was used initially to plan a minimum number of experiments. Statistical analysis, analysis of variance (ANOVA), was also employed to determine the relationship between experimental conditions and yield levels. ANOVA was applied to calculate sum of square, variance, ratio of factor variance to error variance and contribution percentage of each factor on response. The results show that increasing all of parameters improves tensile strength performance. The optimum levels of influential factors, determined for tensile strength are STFIS $200^{circ}C$, SDTFIS 120 min, STSS $225^{circ}C$, SDTSS 120 min, STTS $240^{circ}C$, SDTTS 120 min, STFOS $260^{circ}C$, SDTFOS 60 min, CT $1400^{circ}C$ and CDT 10 min. The results showed that CT and ODTFIS are the most and the less effective factors on response, respectively.