Present study was conducted to investigate the effect of different mulching materials on soil hydrothermal environment and plant growth parameters for potato crop at field experimental station of National Institute of Technology, Hamirpur in the humid sub-tropical agro climate of Western Himalayas. The field experiments were conducted in a randomized complete block design with four mulching treatments; wheat straw mulch, pine needle mulch, rice straw mulch and no mulch in three replications. An increase in soil moisture retention ranging from 5.14% to 42% was observed depending upon the mulch material and depth of the soil layer in root zone. Mulching also reduced the daily maximum soil temperature up to 3.5ºC with an average temperature reduction of 1-2ºC during the period of tuber formation. Mulching produced beneficial effects on root depth, plant height, leaf area index and tuber yield. Mulching helped to bring about a yield surplus of 1.7-4.4 tonnes ha-1 over unmulched conditions and an increase in water use efficiency which varied from 13.5% in rice straw mulch to 34.9 % inwheat straw mulch.