In today’s society there is a growing interest and demand for more environ-mentally friendly alternatives, especially for the textile industry. The textile industry is the industry today that has one of the largest environmental im-pacts when it comes to production and waste, which makes the demand for more environmentally friendly alternatives highly relevant. Denim is a classic garment that was first introduced in 1873 and is a garment that has no limitation of seasons. Denim is well known for its indigo-blue cot-ton in its warp and undyed cotton in its weft. Cotton is the leading fibre used for denim products and there’s an interest to find an alternative for the cotton fibre in several contexts due to the fibres high energy- and water consumption for denim production. This study look into if 50:50 hemp/cotton yarn could be an alternative to denim to minimize the use of cotton. The study will look into the possibility of dyeing hemp/cotton yarn with natural indigo in connection with scouring as a pre-treatment. Furthermore, the study will look into how the characteristics of the yarn changes when being scoured conventionally, scoured in an ultrasonic bath with conventional chemicals, as well as scouring in an ultrasonic bath without any chemicals. To evaluate if the different processes the yarns went through had an effect on the yarns, tensile testing, twist testing and color fastness to rubbing was con-ducted. Additionally, to evalue the results an one-way ANOVA was done to see if the chemicals used had an effect on the twist of the yarns. Conclusion of the study showed that the use of ultrasound assisted pre-treatment for 50:50 hemp/cotton blended yarns showed good results during the mechanical tests, as well as color fastness to rubbing. Compared to the conventionally scoured yarns, no significant differences in results could be apparent. Additionally, the study also shows that the yarns can be dyed with natural indigo, without having to go through a bleaching process.