The letter from Human Rights Foundation (HRF) says the money to pay her comes from "government corruption and human rights violations", reported BBC News.
HRF's Thor Halvorssen says in the letter "your participation in a performance sponsored by a thuggish kleptocratic dynasty involved in gross human rights violations would be improper".
Minaj is due to perform at a Christmas party hosted by mobile phone company Unitel.
Minaj is not the only performer to be criticised by rights groups for their choice of gigs.
In 2011 Nelly Furtado said that she would give away 615,000 pounds she was paid to perform for the family of Libyan leader Muammar Gaddafi.
Representatives for Minaj and the Angolan government are yet to comment.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →*Subscribe to Business Standard digital and get complimentary access to The New York Times
Smart Quarterly
₹900
3 Months
₹300/Month
SAVE 25%
Smart Essential
₹2,700
1 Year
₹225/Month
SAVE 46%
*Complimentary New York Times access for the 2nd year will be given after 12 months
Super Saver
₹3,900
2 Years
₹162/Month
Subscribe
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors
Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share
Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor
Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements
Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
SAVE 25%