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The use of natural fibers from which derived annually renewable resource as reinforcement in composite is provides the positive benefit with respect to environment, ecological advantage and the attractive mechanical properties. Jute fibers are the natural fibers superior on light weight, good mechanical properties with low specific mass, low cost and environmental friendly. Silk fiber is a high tensile strength fiber, good elasticity and excellent toughness. Both natural fibers are commercially available in a continuous fiber type and suitable to fabricate continuous fiber reinforced composite. Pultrusion is a special technique use to shape polymeric composite materials into parts with constant cross section. It is suitable for produce the continuous composite with uniform cross sections, high mechanical properties due to the continuous fiber, mass production and low cost. The reinforcement fibers in the form of continuous fiber are impregnated with matrix and pulled through the heat die to form composites. Therefore putrusion process was selected to manufacture the composite in this research. Usually the pultrusion composite is fabricated by unidirectional fiber and one problem of the unidirectional fiber reinforced composites is the anisotropic of mechanical properties. Braiding technique was introduced to overcome the anisotropic properties since braided fabric can change the braiding angle and selecting number of fiber, therefore the braiding technique can control the degree of anisotropic properties according to the requirements. The design concept of braided composite by pultrusion molding was described to achieve successful implementation of continuous fiber reinforced composite, which consist of materials design, structure design and processing design. Material designs involve the volume fraction and configuration of yarn for intermediate materials with reinforcing fiber and resin. Meanwhile braiding angle, gap between braiding yarns and filling ratio, are the important parameter of the structure design. The processing designs were consisted of molding condition such as molding temperature, pulling speed and pulling force. The objective of this thesis is to investigate the operating parameter to fabricate continuous natural fiber reinforced thermoplastic composite through pultrusion technique in terms of materials, structure and processing design. The manufacturing of tubular braided composite using jute spun yarn and silk fiber reinforced PLA by pultrusion molding was investigated and, braiding technique was used to prepare the tubular preform. The braided fabric consists of fiber bundles called braiding yarns which continuously and spiral oriented along longitudinal direction. The fiber bundle can be inserted between braiding yarns called middle end yarn and angle between braiding yarns called braiding angle. The important structure design parameters of braided composite are braiding angle, gap between the braiding yarn and filling ratio which means the ratio of the volume of fiber and resin to the volume of molding. The tubular preform with only natural fiber was not strong enough for pultrusion, glass fiber was used as the middle end fiber. Thermoplastic resins contain high melt viscosities, which make melt resin impregnation into the reinforcement difficult. For this reason, various intermediate materials have been developed to overcome these problems. The configuration of yarn such as micro braided yarn, paralleled yarn and commingled yarn was investigated to fabricate the tubular braided preforms. The processing parameters were studied and it was clarified that impregnation quality and mechanical properties of composite were increased by increasing the filling ratio. The molding temperature affected the impregnation quality; high molding temperature showed better impregnation property and resulted to increase in the bending modulus. While the bending strength was decreased due to the heat deterioration of silk and jute fiber caused by the molding temperature. The commingled yarn is desirable to achieve better flow of melt resin in molding die and relate to the pultusion speed. Jute spun yarn was mixed with PLA resin fiber and need longer distance for resin flow to fill the fiber bundle and need longer time for impregnation, therefore low speed is appropriated for fabricate jute/PLA tubular braided composite. Meanwhile, silk fibers were commingled with PLA resin fiber and the distance of resin flow is reduced to achieve full impregnate, hence macro-flow occurred around the fiber bundle, however at lower speed macro-flow still continuous and flow out from consolidation state. Therefore higher speed is appropriated for fabricate silk/PLA tubular braided composite. While the speed is increased, the macro-flow was not sufficient to flush the trapped air bubble from consolidation state before the end of taper of molding die, therefore some void occurred in the composite. The designed processing in this thesis could be the step towards the economically viable production of continuous composite by using braiding technique.