The main purpose of this work is to study the mechanical behaviour of three layers composite thick tubes are used in industrial applications by improve the mechanical behavior like burst performance factors N, interface Hoop stress between layers and hoop elastic constants E of composite structures under one type of loads is internal pressure. The composite thick tubes are used in this work are three layers composite thick tubes with two different layer manufacture methods schemes, the first one is three-layer of woven-roving glass fiber reinforced polyester GFRP tubes manufacture in one step with fiber orientation [0°,90°]3 and other is three-layer of woven-roving glass fiber reinforced polyester GFRP tubes manufacture layer by layer with fiber orientation [0°,90°]3 i.e. compound cylinder. To study the effect of layers manufacture method on multi-layer thick tube mechanical behavior as hoop stresses, hoop strain and hoop elastic constants.