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Field experiments were conducted at the University of Arid Agriculture, Rawalpinid during autumn, 2003 and spring, 2004 to document the oil and fatty acid composition of sunflower hybrids in response to temperature variations. Five sunflower hybrids (Super-25, Parsun-1, SMH-9706, Award and Hysun-33) were sown on ten planting dates both in autumn and spring. Experiment design was randomized complete block with split plot arrangements replicated four times. Planting dates were kept in main plots and hybrids in subplots. Sunflower hybrids exhibited significant differences for oil and fatty acid composition. In autumn, amongst hybrids Hysun-33 performed better for oil and oleic acid while Award remained at the top for palmatic and linoleic acid. However, in spring, Super-25 accumulated the highest oil and linoleic acid while Hysun-33 was the best for stearic and oleic acid. Planting dates also influenced oil and fatty acid composition significantly. Overall, spring plantation accumulated higher oil and oleic acid in comparison with autumn planting. However, autumn planting accumulated less oil but higher linoleic acid which depicted an inverse relationship of oleic and linoleic acid. In autumn, late August planting accumulated the maximum linoleic and the minimum oleic acid. In spring, late April planting exhibited the highest oleic and least linoleic acid.