The objective of this study was to develop a model to predict the fiber quality of cotton for each position across the main stem nodes. The cultivar used in this study was DES119. Research fields were planted in the Experimental Farm of Mississippi State University. The model was based on the data collected in 1993. The fiber properties considered were: fiber length (upper quartile length by weight), microafis values and fiber strength. The fiber length and the microafis values were analyzed by using the Advance Fiber Information System (AFIS) machine. The fiber strength, however, was analyzed by using the Stelometer instrument. To reduce the variability of the fibers among different locks of each boll, only lint from the middle seed of each lock from the same boll were combined and analyzed to obtain the properties of that boll. Results indicated that the higher along the main stem node a boll is produced, the lower will be the values of the properties. It was also noted that the closer the bolls were to the main stem, the larger were the values of the properties. Based on these trends and for each fiber property, a modified decay model was developed and fitted to the data across the main stem nodes. The parameters involved were then generalized across the branch nodes. The results showed good agreement between the actual and predicted values.