The present research work regarding the "Comparative study of D-slot and straight slot in compact spinning system under different mechanical variables" was initiated in the Department of Fibre & Textile Technology, University of Agriculture Faisalabad and was conducted at Crestex Mills Limited Sargodha Road Faisalabad. Standard techniques were applied for technological evaluation of the results. The samples were spun into the yarn of 40S count at Rieter K-44 compact frames of multiple processing variations. The results related to yarn characteristics along with their statistical manipulation are briefly discussed in this book.