Rainbow trout (Oncorhynchus mykiss) is a low volume and high value sport fish of coldwater therefore; production of sterile triploid rainbow trout is the major concern for its production enhancement and ecological biodiversity management in coldwater. Experimental trials of heat shock treatment to fertilized eggs for triploid induction in rainbow trout were conducted at three different sites. Fifteen healthy brooders for each operation were used to get fertilized eggs to get exposed to heat shock. Delay timing for thermal shock after fertilization, temperature for thermal shock treatment to retain the second polar body and exposure time of treatment were standardized for success of triploidy induction. For better triploid induction rate (TR) heat shock treatment at 280C for 10 minutes can be applied to green eggs. A success rate at 80 % of triploidy induction in rainbow trout is possible with 40-46% hatching rate and 57-68% while 74% hatching rate and 72-80% survival in diploid stock was observed at similar environmental conditions upto swim up fry stage. For verification of triploidy induction Karyotyping of fry after yolk absorption and erythrocytes measurements was applied. In treated group, three sets of chromosomes (86-90) were observed in chromosome plates. Erythrocytes measurement (µm) reflects the 13% larger cell size and 12% larger nucleus in triploids over the diploids. There is 9-19% better growth in triploids over the diploids in different rearing conditions at fingerlings stage in a field study of 90 days. The survival of triploids fingerlings was observed as 48-68%, while it was 62-72% in diploid stock. Accuracy of heat shock treatment and better rearing conditions are required for success of triploids production. The produced triploids were used for the stocking of hill stream and found better growth of the yearlings in natural condition. Aqua tourism has a great potential for its contribution to main stream economy of Himalayan states. Triploids fingerlings were reared in the raceways and found 17% better growth over the diploids. Due to extra genetic material triploid rainbow trout remain more heterozygous and exhibits enhanced growth and survival. Triploid rainbow trout has superior performance traits as compared to their diploid counterparts and will negate production losses due to early sexual maturation and related reduction in somatic growth.The technology would be helpful for promotion of trout based aqua tourism and better practice of trout aquaculture for livelihood support to the people dwelling in hills. The work was conducted under DBT sponsored project.