Abstract: An experiment is designed for freshmen physics laboratory course. Using a student He-Ne （632.8 nm） laser and simple experimental setup, we observe up to 9th order rainbows and the Alexander＇s dark band between the primary and secondary rainbows. The formation of multiple rainbows is demonstrated vividly. The position of higher-order rainbows is in good agreement with the theory.

Key words: multiple rainbows, Alexander＇s dark band, minimum deviation angle