But the majority of the time he is uncredited.
- Che gioia vivere .... Officer at airship launch (uncredited)
- Il pianeta degli uomini spenti .... United Commission representative (uncredited)
- Il Re di Poggioreale .... Professor who asks for penicillin (uncredited)
- Una vita difficile .... Eccellenza, party guest (uncredited)
1962 - Boccaccio '70 .... Restaurant diner (uncredited)
- Il sorpasso .... Man waiting in toilet door (uncredited)
- L'orribile segreto del Dr. Hichcock .... Laboratory specialist (uncredited)
- La marcia su Roma .... Professor Bellinzoni (credited as "Howard Rubiens")
- Maciste all'inferno .... Villager (uncredited)
1963 - I 4 tassisti .... Man asking questions (uncredited) (uncertain identification)
- Il Gattopardo .... Don Diego (credited as "Howard N. Rubien")
- Maciste contro i Mongoli .... Mongol elder at Khan's funeral (credited as "Rubien Howard")
1964 - Extraconiugale .... Man in Renato's home movie (uncredited)
1965 - Due mafiosi contro Goldginger .... General (uncredited)
- Io uccido, tu uccidi - segment "Giochi acerbi" .... The count, a guest at the memorial service (uncredited)
1966 - Bel Ami 2000 / 100 ragazze per un playboy .... Party guest (uncredited)
- Che notte ragazzi! .... Brown the elder (uncredited)
- Io, io, io... e gli altri .... Politician (uncredited)
- Ramon il Messicano .... The doctor (uncredited)
- Requiem per un agente segreto .... The professor (uncredited)
- Scusi lei è favorevole o contrario? .... Party guest (uncredited)
1967 - Killer kid .... El Santo (credited as "Nelson Rubien")
1969 - Cuore di mamma .... Dean of the university (uncredited)
- La caduta degli dei .... General (credited as "H. Nelson Rubien")
1971 - Morte a Venezia .... Hotel guest (uncredited)
- Stress .... Marquis (uncredited)
1972 - Fratello Sole, Sorella Luna .... Priest (uncredited)
- L'età di Cosimo de' Medici (TV mini series) - ep. 3 .... Giorgio Gemisto Pletone (credited as "Honard Nelson Rubien")
- Ludwig .... Ambassador (uncredited)
1973 - Canterbury n.2 .... First storyteller (uncredited)
- Pane e cioccolata .... Restaurant customer (uncredited)
- Tutti figli di mammasantissima ... Corrupt senator (uncredited)
1975 - Mahogany .... Man at fashion show (uncredited)
1976 - A Matter of Time .... Disgruntled hotel guest (uncredited)
- Cassandra Crossing .... Train passenger (uncredited)
- Cuore di cane .... Professor's guest (credited as "Nelson Rubien")
- L'innocente .... Party guest (uncredited)
- Oh, Serafina! .... Grandfather of Augusto Valle (uncredited)
- Spogliamoci così senza pudor .... Friend of the Partibon family (uncredited)
1978 - Le braghe del padrone .... Elegant man in car (uncredited)