The purpose of this study is to determine the spatial thinking ability of high school students using indicators from Sharpe-Huynh model. These indicators include analysis, spatial interaction, scale, representation, comprehensiveness, and application. Furthermore, this study examined the effect of Earthcomm learning on student's spatial thinking ability. This study research employs a quantitative study, utilizing a quasi-experimental design with a non-equivalent control group. The study is conducted among school students in Padang City, West Sumatera Province, Indonesia. The research population consisted of 287 students, divided into eight research groups. Data on students' spatial thinking ability were collected through the Sharpe-Huynh model of spatial thinking ability test. Before further analysis, the data were assessed for normality and homogeneity. The experimental group utilized earth science in the community (Earthcomm) learning model, while the control group employed conventional learning. The research data were analyzed using Mann-Whitney U test. The findings revealed that the spatial thinking ability of high school students ranged from low to moderate. The Earthcomm learning model demonstrated a significant impact in improving spatial thinking skills. The impact of Earthcomm learning on enhancing spatial thinking abilities among high school students is elaborated in the following article.