<p>Climate change and its impacts are increasing, which requires the timely implementation of adaptation measures. This study aimed to assess smallholder farmers’ perceptions of climate change and determinants in the adoption or choice of adaptation strategies in the upper Gelana watershed, located in the northeastern highlands of Ethiopia. This research employed mixed research methods, involving both qualitative and quantitative approaches. Empirical data were gathered from 165 randomly selected households using structured questionnaires, complemented by 12 key informant interviews to provide in-depth qualitative insights. We used descriptive statistics, chi-square test and multivariate probit (MVP) models to analyze the data. The findings revealed that a significant proportion of farmers in all agroecological zones (AEZs) perceive increasing temperature and declining precipitation. However, key informants noted a decreasing trend in rainfall, mainly observed in the <i>belg</i> season. The majority of the respondents also perceived an increase in the occurrence of drought, disease incidence, erosion hazards, pests, and a decline in crop yields due to climate change and variability. There is a significant variation in the adaptation strategies to climate change implemented across the AEZs particularly in soil and water conservation (SWC), agroforestry, and irrigation. The MVP models indicated that farming in the lower and upper <i>Weina Dega</i> AEZs, education status, extension support, and access to climate information significantly affect the choices of most climate adaptation strategies in the study area. The findings will help improve climate adaptation measures by leveraging the positive contributions of agroecology, demographic, socioeconomic, and institutional factors and addressing negative influences, ultimately benefiting stakeholders in the upper Gelana watershed.</p>