Process for dehydrogenation of a hydrocarbon feedstock of paraffins at a pressure of between 0.02 and 2 MPa, at a temperature of between 400 and 800°C, a mass rate of the feedstock treated by unit of mass of catalyst between 0.5 and 200 kg(kg cat.h) and a hydrogen/hydrocarbon molar ratio between 0 and 20, in the presence of a catalyst that comprises a noble metal M of platinum having a content of from 0.01 to 10 % by weight, at least one promoter X1 that consists of tin, having a content of from 0.005 to 10 % by weight, an alkaline or alkaline-earth compound, and a porous substrate, in which the X1/M ratio is between 0.3 and 8, the Hir/M ratio that is measured by hydrogen chemisorption in an irreversible way as described in the specification is more than 0.40, and the bimetallicity index BMI that is measured by hydrogen/oxygen titration as described in the specification is more than 108, and which the process for the preparation of the catalyst comprises the following stages: a) introduction of the promoter X1 in the substrate or on the substrate in a content of from 30 to 70% by weight of the total quantity of X1, b) optional drying stage of the product that is obtained at the end of stage a), c) calcination of the product that is obtained in stage a) or optionally in stage b) at a temperature that is preferably between 350 and 650°C, d) deposition of platinum, e) optional drying under neutral atmosphere or atmosphere containing oxygen, at a moderate temperature that preferably does not exceed 150°C, f) deposition of a complementary fraction of the promoter X1, in a content of from 30 to 70% by weight of the total quantity of X1, on the product that is obtained in stage d) or e), said complementary fraction being deposited by bringing into contact a solution of tin tetrachloride, g) optional drying of the product that is obtained in stage f), h) calcination of the product that is obtained in stage f) or g), this calcination is preferably conducted in the presence of air, and this air can also be enriched with oxygen or nitrogen, m) deshalogenation in gaseous phase in the presence of an oxygen fraction that exceeds 2% by volume, at temperatures of between 300°C and 600°C so as to obtain a final halogen content of between 300 and 1000 ppm by weight, n) introduction of the alkaline or alkaline-earth compound, o) optional drying under neutral atmosphere or containing oxygen, at a moderate temperature, of the product obtained in step n), p) calcination of the product obtained in step n) or o), said calcination being conducted in the presence of air, and this air can be enriched with oxygen or nitrogen. a) introduction of the promoter X1 in the substrate or on the substrate in a content of from 30 to 70% by weight of the total quantity of X1, b) optional drying stage of the product that is obtained at the end of stage a), c) calcination of the product that is obtained in stage a) or optionally in stage b) at a temperature that is preferably between 350 and 650°C, d) deposition of platinum, e) optional drying under neutral atmosphere or atmosphere containing oxygen, at a moderate temperature that preferably does not exceed 150°C, f) deposition of a complementary fraction of the promoter X1, in a content of from 30 to 70% by weight of the total quantity of X1, on the product that is obtained in stage d) or e), said complementary fraction being deposited by bringing into contact a solution of tin tetrachloride, g) optional drying of the product that is obtained in stage f), h) calcination of the product that is obtained in stage f) or g), this calcination is preferably conducted in the presence of air, and this air can also be enriched with oxygen or nitrogen, m) deshalogenation in gaseous phase in the presence of an oxygen fraction that exceeds 2% by volume, at temperatures of between 300°C and 600°C so as to obtain a final halogen content of between 300 and 1000 ppm by weight, n) introduction of the alkaline or alkaline-earth compound, o) optional drying under neutral atmosphere or containing oxygen, at a moderate temperature, of the product obtained in step n), p) calcination of the product obtained in step n) or o), said calcination being conducted in the presence of air, and this air can be enriched with oxygen or nitrogen.