Despite their high potential for social interaction, semi-university streets have often lost their social function, transforming into mere transit corridors with low attractiveness due to poor paving quality, a lack of pause spaces, uncoordinated building facades, and inadequate lighting. This study aims to provide urban design strategies for improving the environmental quality of such corridors using a walkability approach, focusing on a case study of Heidarkhani Street in the Narmak neighborhood of Tehran. The research employs an applied, descriptive-analytical methodology. Data were collected through library studies, field observations (physical and behavioral), and surveys using a Likert-scale questionnaire distributed among students, residents, and local shopkeepers. The data were then analyzed using statistical methods and multi-criteria decision-making (MCDM) models. The findings indicate that Heidarkhani Street holds a vital communicative position due to its connection between the Iran University of Science and Technology and the metro station; however, it faces significant challenges such as sidewalk obstructions and a decline in nighttime vitality. The main identified strategies include: reducing the vehicular carriageway width, upgrading paving quality, creating bicycle lanes, enhancing active ground-floor facades, organizing urban furniture and pause spaces, improving lighting, and regulating informal activities. The results indicate that through the implementation of targeted physical-functional interventions and integrated space management based on the proposed design framework, this street possesses high potential to be transformed into a walkable, safe, vibrant corridor with a distinct identity, capable of fostering social interactions.