We conceptualize two distinct post-acceptance usage behaviors: (1) routine use (RTN) refers to the use of information system (IS) consistent with normal work processes and (2) innovative use (INV) means users’ applying system features in novel ways. While RTN helps integrate the implemented IS into work processes, INV further extracts the value of the IS. Drawing on motivation theory, we propose a tri-dimensional intrinsic motivation (3D-IM) construct and hypothesize about the differential roles of intrinsic motivation (IM) and extrinsic motivation (EM) in explaining RTN and INV. Our first study confirms the measurement model of 3D-IM and illustrates its superior predictive power over perceived enjoyment, a typical measure of IM in prior literature. Study 2 reveals the differential impacts of IM (measured as 3D-IM) and EM (measured as perceived usefulness) on INV and RTN. Specifically, relative to EM, IM has a stronger effect on INV but a weaker impact on RTN.