UFC 291稱重精華，本卡共有兩人超重。

“天秀哥”米歇爾·佩雷拉(Michel Pereira)：174磅，超3磅；梅根·奧利維 (Megan Olivi) 在稱重對視前宣布，天秀對陣“天秀哥”米歇爾·佩雷拉(Michel Pereira)的比賽取消了。

維尼修斯·薩爾瓦多（Vinicius Salvador）：128.5磅，超出2.5磅；罰20%出場費(fèi)給CJ·維加拉(C.J. Vergara)，比賽繼續(xù)

UFC 291選手完整版稱重結(jié)果如下：

Dustin Poirier (155) vs. Justin Gaethje (156)

Jan Blachowicz (205) vs. Alex Pereira (205.5)

Michel Pereira (174)* vs. Stephen Thompson (170.5)

Tony Ferguson (155) vs. Bobby Green (155.5)

Michael Chiesa (170) vs. Kevin Holland (169.5)

Gabriel Bonfim (170) vs. Trevin Giles (170)

Derrick Lewis (263.5) vs. Marcos Rogerio de Lima (262)

Roman Kopylov (185) vs. Claudio Ribeiro (185.5)

Darrius Flowers (170.5) vs. Jake Matthews (170)

Vinicius Salvador (128.5)** vs. CJ Vergara (125.5)

Uros Medic (170.5) vs. Matthew Semelsberger (169.5)

Priscila Cachoeira (125) vs. Miranda Maverick (125.5)