This paper concerns with a generalization of Szász-Baskakov operators, which includes Boas-Buck-type polynomials. The convergence properties are studied in weighted space and the rate of convergence is obtained by using weighted modulus of continuity. A Voronovskaya-type theorem is investigated. Also, the theoretical results are demonstrated by choosing the particular cases of Boas-Buck-type polynomials, namely Appell polynomials, Hermite polynomials, Gould-Hopper polynomials, Laguerre polynomials and Charlier polynomials.