Sustainability is one of the main challenges facing the fashion industry. Although the awareness of sustainable fashion has been increased, the sustainable design still lacking the innovation. Therefore, the contribution to the sustainable fashion should not be limited to sustainable solutions to a previously existed designs, but also to create a new and innovative designs. The objectives of this study are twofold: (1) to create a transformable women's dress by integrating sustainability practices and modular design concept, and (2) to evaluate the functional and aesthetic aspects of design by professionals in the fashion field (designers and professors). The study procedures consist of two stages – design experiments, and online surveys. In stage one, several units inspired by snowflake were drawn using Adobe Illustrator. Then, these units were digitally printed on a velvet fabric to be laser cut and connected to create a transformable design. In second stage, the transformable design was evaluated by 41 professionals. A descriptive quantitative method was used to analyze the data. The results show that the professionals' perceptions were positive related to design versatility, cohesion, fit, function, and aesthetics. Moreover, the result concluded the appropriate of using modular design approach and the laser cutting techniques in the fashion industry to accelerate progress towards sustainable fashion. The study provides an application of modular approach to create a sustainable transformable design. Fashion designers should explore modular approach and laser cutting to design transformable garments using different fabrics and materials that increase wearability and versatility.