Key words fuzzy randomness, fuzzy random variable, fuzzy random function, fuzzy stochastic finite element method. MSC (2000) 03E72, 60G07, 60K40, 74S05The formal description of data uncertainty as fuzzy randomness combines randomness and fuzziness in an uncertain model. This generalized uncertainty model permits the simultaneous consideration of randomness, fuzziness and fuzzy randomness. Variables and functions with the property of fuzzy randomness are introduced. The formulation of the latter using α-levels and fuzzy bunch parameters permits the application of fuzzy randomness in the numerical simulation of engineering problems. The finite element method is extended by the inclusion of fuzzy randomness to yield the fuzzy stochastic finite element method (FSFEM). Examples demonstrate the advantage of the chosen formal description in practical applications.