Samatta needed only four minutes to open the scoring as he fired the hosts into the lead after breaching a napping Botswana backline.
Ibrahim Ajib came close to doubling the Taifa Stars’ lead midway through the first half, but saw his well struck free kick narrowly miss the target.
Mogakolodi Ngele came closest to drawing the visitors level as Tanzania took their lead in at the break.
Simon Msuva missed two great chances in succession in the early stages of the second-half as the Taifa Stars looked to put the match beyond their guests.
After an interchange of opportunities through the second half, Samatta struck again for Tanzania to seal the 2-0 victory with an 88th-minute free-kick.
The Belgium-based attacked left Kabelo Dambe rooted to his feet with an absolute cracker of a set piece.
Samatta is currently in a form of his life having already netted 17 goals for Genk in the Belgian Jupiler League, Europa League and Belgian Cup, and Saturday's brace was the 24-year-old former TP Mazembe star’s tenth strike in 2017.
Tanzania will next take on Burundi in another international friendly at the Benjamin Mkapa National Stadium also in Dar es Salaam on Tuesday the 28th of March.