Springs are drying and rainfall patterns are changing in the Himalayas, resulting in water scarcity for agriculture. We examine the adoption of rainwater harvesting, a technology that has been recently re-designed and re-introduced to farmers in Nepal, as a climate change adaptation strategy in mountain farming. Using farm household surveys, we examine the impact of the adoption of rainwater harvesting on farm income and profitability. The adoption of the technology is mostly driven by external support such as farmers training that more than tripled household agricultural and livestock income. With incremental annual benefits of US$700 on average per adopter, this technology is economically viable from a household perspective. Adopters benefit from an increased supply of irrigation water during the dry season, which allows them to diversify their crops from subsistence cereal production to commercial high-value vegetables. Our analysis suggests that if 10% of households in an average rainfed district receive farming-related training, the net benefits in the district would be approximately US$1.3 million per year from the adoption of rain water harvesting technology. Given climatic and weather-related uncertainties faced by rainfed agriculture in the hills of Nepal, this technology is potentially a very useful climate change adaptation strategy for community resilience in the hills of Nepal.