A process for the preparation of a 2,2-disubstituted pentane-1,5-diamine of the formula I (see formula I) where R1 and R2, independently of one another, are C1- to C10-alkyl or C2- to C10-alkenyl or together are a C4- to C7- alkylene chain which is unsubstituted or monosubstituted to pentasubstituted by C1- to C4-alkyl, from a 2,2-di- substituted 4-cyanobutanal of the formula II (see formula II) where R1 and R2 are as defined above, comprises, in two spatially separate reaction spaces, a) reacting the 4-cyanobutanal of the formula II, in a first reaction space, with excess ammonia on an acidic heterogeneous catalyst at from 20 to 150.degree.C and at from 15 to 500 bar, and b) hydrogenating the resultant reaction product, in a second reaction space, using excess hydrogen in the presence of excess ammonia on a catalyst containing cobalt, nickel, ruthenium and/or another noble metal, if desired with a basic component or on a basic or neutral carrier, at from 60 to 150.degree.C and at from 50 to 500 bar. 2,2-Disubstituted pentane- 1,5-diamines of the formula I' (see formula III) where R1' and R2', independently of one another, are C1- to C10-alkyl or C2- to C10-alkenyl or together are a C4- to C7-alkylene chain which is unsubstituted or monosubstituted to pentasubstituted by C1-to C4-alkyl, with the proviso that R1' and R2' are not simultaneously methyl are also described.