"Research Findings:" Although the importance of block play to children's spatial ability has been recognized globally, little is known about children's use of spatial frames of reference during spatial processing. This study investigated the intervention with guided block play to promote children's use of their intrinsic frame of reference, an identified effective frame of reference for spatial information. Participants included 42 kindergarten children (M[subscript age]=67.12 months, SD = 3.91, 48% girls) and 42 pre-kindergarten children (M[subscript age]=55.80 months, SD = 3.63, 57% girls) from one public kindergarten in Shanghai, China. A quasi-experiment method was used with a four-month intervention program designed for the experiment groups. Statistically significant differences were identified in the performance of the spatial tasks between the experiment and control groups in both kindergarten and pre-kindergarten children after the intervention. The results revealed that block-play interventions can effectively increase children's ability to use their intrinsic frame of reference and their preference in using this frame for spatial representations. "Practice or Policy:" These findings provided a new perspective on analyzing children's spatial competence and supported the benefits of block play interventions with empirical evidence.