The Thai team, ranked second in the world, produced a superb display to claim an impressive 18-1 victory over hosts and defending champions Great Britain in the semi-final.
Having started the day with an 11-1 victory over Brazil in the last eight, the team of Witsanu Huadpradit, Mongkol Jitsa-Ngiem, Pattaya Tadtong and Watcharaphon Vongsa proved far too strong for their British counterparts as they closed out the match in style.
The Thais took a maximum six points in the fourth end on their way to one of the most conclusive victories of the London 2012 Paralympic Games Boccia tournament so far.
China will provide the surprise opponents for Thailand in Tuesday's final, after the number-seven ranked team followed up their victory over Republic of Korea by beating Portugal.
China had to come from behind to win as Portugal led 4-1 after four ends, but China levelled after the fifth end and added a further two points for a 6-4 victory.
Elsewhere, impressive Brazilian pair Eliseu Dos Santos and Dirceu Pinto were made to work hard by Host Nation hopefuls Stephen McGuire and Peter McGuire before triumphing 3-2 in the Mixed Pairs - BC4 class.
They will now face the Czech Republic in the gold-medal decider, after the team of Radek Prochazka and Leos Lacina overcame a deficit and then won a decisive tie-break to beat Canada.
In the Mixed Pairs - BC3 class, Greece produced a consistent display to overcome Belgium with a 7-0 victory.
They will face Portugal, who edged out Republic of Korea 4-3 in the second semi-final.