The world body's postal agency released the stamp designed by Miami-based artist Ferdie Pacheco marking the International Day of Non-Violence.
The one dollar stamp portrays the Indian freedom fighter in red, blue and gold.
The envelopes marked with the stamp and the United Nations' seal were on sale at a function organised by the Indian Mission to celebrate Gandhi's birth anniversary
Many UN envoys spoke on the influence of Mahatma Gandhi's life during the program.
"Gandhi had influenced millions of Americans. Gandhi believed that physical force could be turned aside by moral forces," US envoy to the UN Susan Rice said.
While President of the General Assembly Ali Treki stressed upon Gandhi's commitment to communal harmony, Hardeep Singh Puri India's ambassador to the UN spoke on how Mahatma Gandhi previsioned the UN.