Yarn breakages have a great effect on weaving productivity and also on fabric quality. The most important factors affecting the air jet weaving machine‟s efficiency are warp and weft breaks which are strongly connected to the yarn parameters. It was determined that the yarn properties, which mostly affect the rates of both warp and weft breaks are yarn strength, yarn imperfections (thin places, thick places, neps), yarn twist, yarn hairiness and unevenness. The main causes of both weft and warp yarn breakages in weaving are poor yarn quality, excessive loom speed, uncontrolled room temperature and relative humidity, uncontrolled warp tension, mechanical problems of the machine, and Other causes can be due to bad knots on warp yarn, poor size pick-up, loose ends, fly stuck onto threads, snarls after weft pre feeder, snarls on cone, improper cone forming, slough off at cone, wrong drawing–in, damaged back rest roller, healed frames, drop wires and improper warp beam forming. The breakage study was conducted using air jet looms at BDTSC. When weaving for a period of one hour at a loom speed of 600 rpm, using a reed width of 1.6 m, and producing a plain fabric with 24 ends/cm and 18 picks per centimeter number of warp and weft breaks for 100% cotton yarn. Minitab 15 software was used for analyzing the experimental data. Analysis of Variance (ANOVA) was used to detect the significant effects of these variables. The breakage rate of unconditioned yarn is greater than conditioned yarn. Since conditioning improves yarn qualities (like; strength, elongation, etc.).