解答:解:如图,圆(x+1)2+y2=3的圆心为M(-1,0),圆半径|AM|= 3 ,圆心O(-1,0)到直线x+y-1=0的距离:|MC|= |?1+0?1| 2 = 2 ,∴直线x+y-1=0被圆(x+1)2+y2=3截得的弦长:|AB|=2 ( 3 )2?( 2 )2 =2.故答案为:2.