Experimental study was conducted to obtain the air velocity profiles in turbulent pipe flow. The acrylic smooth pipe (${phi}=80mm$) was used for the test section of the flow loop. It was known that the velocity profiles of turbulent flow were different with Reynolds numbers and the viscous sublayer was usually quite thin. The following conclusions were drawn from the experimental investigations. Maximum velocity of the pipe center and flow-rate are useful for the duct design on the spot. The velocity profiles of high Reynolds number was flatter than those of low Reynolds number. It was known that the exponent, n, for power-law velocity profiles was $6{sim}9$ depending on Reynolds number ranging from $10^4$ to $10^5$ in the turbulent flow, However, in this experiment study, it was $9{sim}14$ depending on Reynolds number ranging from 17,000 to 123,727 in the turbulent flow, and $1.7{sim}3.5$ depending on Reynolds number ranging from 2,442 to 4,564 in the transition region.