Yaƙin Franco-Siamese na 1893, wanda aka sani a Tailandia da Lamarin RS 112 rikici ne tsakanin Jamhuriya ta Uku ta Faransa da Masarautar Siam.Auguste Pavie, mataimakin jakadan Faransa a Luang Prabang a shekara ta 1886, shi ne babban jami'in inganta muradun Faransa a Laos .Abubuwan da ya yi, waɗanda suka yi amfani da raunin Siamese a yankin da kuma mamayewar da 'yan tawayen Vietnamese suka yi daga Tonkin na lokaci-lokaci, ya ƙara tashin hankali tsakanin Bangkok daParis .Bayan rikicin, Siamese sun amince su mika Laos ga Faransa, aikin da ya haifar da fadada Indochina na Faransa.A cikin 1896, Faransa ta rattaba hannu kan wata yerjejeniya da Biritaniya da ke fayyace iyakar Laos da yankin Birtaniyya a Burma ta sama.Masarautar Laos ta zama mai karewa, da farko an sanya shi ƙarƙashin Gwamna Janar na Indochina a Hanoi.Pavie, wanda kusan shi kadai ya kawo Laos karkashin mulkin Faransa, ya ga hukuma a Hanoi.