下表列出了所有的Lua语言支持的关系运算符。假设变量A持有10和变量B持有20则：

示例

试试下面的例子就明白了所有的Lua编程语言提供的关系运算符：

a = 21

b = 10

if( a == b )

then

   print("Line 1 - a is equal to b" )

else

   print("Line 1 - a is not equal to b" )

end
if( a ~= b )

then

   print("Line 2 - a is not equal to b" )

else

   print("Line 2 - a is equal to b" )

end
if ( a < b )

then

   print("Line 3 - a is less than b" )

else

   print("Line 3 - a is not less than b" )

end
if ( a > b ) 

then

   print("Line 4 - a is greater than b" )

else

   print("Line 5 - a is not greater than b" )

end
-- Lets change value of a and b

a = 5

b = 20

if ( a <= b ) 

then

   print("Line 5 - a is either less than or equal to  b" )

end
if ( b >= a ) 

then

   print("Line 6 - b is either greater than  or equal to b" )

end

当建立并执行上面的程序它会产生以下结果：

Line 1 - a is not equal to b

Line 2 - a is not equal to b

Line 3 - a is not less than b

Line 4 - a is greater than b

Line 5 - a is either less than or equal to  b

Line 6 - b is either greater than  or equal to b