Yes, negative numbers can be rational numbers. A rational number is any number that can be expressed as the quotient or fraction of two integers, where the denominator is not zero. Negative numbers that can be written in this form, such as -3/4 or -5, are considered rational because they fit the definition of a rational number.
In short, negative numbers like -1, -3/5, and -7/2 are all rational numbers because they can be written as fractions with integers.