Abstract Public spaces facilitate opportunities for social interaction and promote social life. The social-spatial complexity of public spaces can be explored through the relationship between built forms and users’ daily social activities. The contemporary needs of users have retrofitted or replaced the controversial public spaces such as streets, depriving the prime function of sustaining and facilitating social life. Thus, any factors influencing users’ social/public life impact the quality of public spaces. Also, contextualization and definition of public spaces necessitate an evaluation of their quality. The lack of a quality assessment directory (QAD) for evaluating multi-functional public spaces motivated us to address it. To achieve the aim, this research has conducted a systematic literature review applying the content analysis to explore the principles and indicators influencing and enhancing social interactions in multi-functional public space design and then performed a normalization analysis to measure the weight of each indicator. The QAD constitutes five criteria (C1 – Inclusiveness, C2 – Desirable activities, C3 – Comfort, C4 – Safety, C5 – Pleasurability), and forty-two (42) embedded sub-criteria. The research found that Inclusiveness (Wn C1 = 4.38) and Pleasurability (Wn C2 = 3.88) have received the highest weights. Also, the research found that the sub-criteria ‘Physical/visual connection or openness to adjacent spaces’ (Wn Sc.4.1 = 1.00), ‘Users of diverse ages’ and ‘Community gathering third places’ (Wn = 0.750) have received the highest weights. Using such a QAD, urban professionals can quantify the effectiveness and efficiency of public spaces’ environmental and physical qualities in promoting social interactions and sociability.