Growers are questioning the merits of conventional high-input production agriculture. This study compares the effects of input level and cropping diversity on direct and indirect non-renewable energy inputs, energy outputs, and energy use efficiency for 9 cropping systems (all 6 years in length) in west-central Saskatchewan. The treatments included 3 levels of input use (High - recommended rates of fertilizers and pesticides as required; Reduced -reduced rates of fertilizer, pesticides, and tillage; and Organic -non-chemical pest control, legume green manure, and later seeding) and 3 levels of cropping diversity [LOW -monoculture cereals; DAG -diversified using oilseed and pulse grains; and DAP -diversified using annual grains and perennial forages]. Based on data from 1996 to 2003, our results showed that Organic Input systems used 62% less non-renewable energy and had higher energy output/energy input ratios (8.2 vs 6.6) compared to High and Reduced Input systems, but they also produced about 45% less energy output because of lower crop yields. Gross energy output was highest for the DAG systems, and intermediate for LOW and DAP (about 13% less). Fertilizers (primarily N) and fuel were the major energy inputs for all treatments, except for Organic treatments where fuel alone was the major energy requirement. Treatments that included pulse crops required lower total energy inputs and returned higher energy output and energy use efficiency than those that included mainly cereals.