Concrete is one of the materials widely used in construction work. Construction work that uses concrete mixtures as its basic material, may have problems that can cause a delay in the casting process. Late casting process can cause a cold joint (cold connection) which will appear on the surface of the old concrete layer with a new concrete layer considering the short concrete time setting. This study aims to analyze the effect of the horizontal cold joint with the compressive strength of the concrete produced. The concrete uses additional materials in the form of polypropylene fibers which are expected to increase the value of concrete compressive strength under cold joint conditions. The results of normal concrete compared to polypropylene fiber joints at the age of 28 days with a 120 minutes casting interval showed an increase in compressive strength of 7.08% for vertical direction polypropylene fiber joints and a decrease in compressive strength of 30.01% for cold joint polypropylene fibers horizontal direction. While polypropylene fiber joint cold concrete with a casting time of 240 minutes compared to normal concrete showed a decrease in compressive strength of 10.82% for vertical direction polypropylene fiber joints and 33.33% for horizontal direction polypropylene fiber joints. The results of the effect of 120 and 240 minutes casting interval on the compressive strength of cold joint polypropylene fibers in the vertical and horizontal directions decreased. The decreasing the influence of the old-time casting interval in the vertical direction is 16.72% while the horizontal direction is 4.72%. This study showed that the longer the casting interval decreases the compressive strength of the concrete and the addition of fiber in the mixture can increase the concrete compressive strength.