Shape of aggregate plays a crucial role in the volumetrics and mechanical behavior of dense hot mix asphalt (HMA). Shape indexes based on ratios of aggregate dimensions are generally recommended to restrict the presence of undesirably shaped aggregates in HMA. Suggesting an over-stringent limit on aggregate shape may result in mounting burden on natural resources. Therefore, criteria to reject aggregate that may be otherwise of sound quality should be carefully selected. In this paper, four different aggregates with varying strength properties were used to study the effect of different proportions (0, 30, 60 and 100%) of flaky or elongated (FE) aggregates on the volumetrics, aggregate breakage and resilient modulus (MR) of HMA. Effect of FE aggregates on volumetrics was studied through Marshall mix design process. It was observed that presence of FE aggregates up to 60% does not have any significant impact on volumetrics of HMA, especially optimum binder content (OBC) to reach design air voids. Aggregate breakage was higher for weaker aggregates and it increased with the increase in FE aggregate proportion. Presence of FE aggregates up to 60% was found to increase the MR of HMA by at least 50% except when weak aggregate was used. Results indicate that placing specification limit based on shape index that restricts the percent of FE aggregates less than 60% may be relaxed, provided the aggregates have good strength. Superpave recommendation of maximum 10% of aggregates greater than 5:1 max–min dimensional ratio was found more appropriate for restricting aggregate shape proportion in HMA.