Simultaneous heat transfer and friction factor experiments for plain and micro-fin tubes were conducted in our previous study. The results showed that the heat transfer characteristics of the micro-fin tubes were the same as for the plain tube. However, the friction factor characteristics of the micro-fin tubes in the transition region were different compared to the plain tube. This type of friction factor data cannot be easily correlated by the traditional regression method. Therefore, a logistic dose-response curve-fitting method is proposed in this study. This particular method has recently been used by other researchers in correlating the friction factor data in plain tubes. In this study, three sets of micro-fin tubes friction factor data with different inlets from our previous study were correlated by the logistic dose-response curve-fitting method. All the fully developed friction factor data for the entire flow regime were predicted by a composite logistic dose-response function within ±11% deviation. The majority of the data (over 85%) was predicted with less than ±5% deviation. © 2014 Taylor and Francis Group, LLC.