Abstract: Teacher learning is mediated by context. Teacher learning occurring in community is characterized as experiential, participative learning and a process of identity formation. However, teacher community with clearly-defined boundary is likely to undermine teacher professional development. School-university partnership can expand teacher learning sites. In this partnership, the boundary is ambiguous, open and inclusive, allowing diverse participants to exchange with each other through multiple discourse practices. In this context, teacher learning involves a process of problem-solving and inquiry, which helps to produce new knowledge and improve the teaching system. Both the development and utilization of boundary objects and boundary crossers are the mediating mechanism to facilitate teachers’ boundary crossing learning. One of the important research topics in the field of teacher learning is how to connect boundary learning in partnership with learning in community.