Romanization of Japanese refers to the romanization of Japanese words, which are written in kanji and kana in Japan. Japanese may be romanized for street signs for foreigners, transcription of names, and in dictionaries and textbooks for learners of the language.

There are a number of different romanization systems. The three main ones are Hepburn romanization, Kunrei-shiki (ISO 3602), and Nihon-shiki (ISO 3602 Strict). Variants of Hepburn are the most widely used.

All Japanese who have attended elementary school since the war have been taught to read and write romanized Japanese, called rōmaji (ローマ字, rōmaji) ("Roman letters") in Japanese. Romanization is also the most common way to input Japanese words into word processors and computers. Therefore, other than a small segment of the older population, most Japanese are able to read and write using rōmaji, although apart from textbooks for learners of Japanese it is rare to find complete sentences written in it.

The list below shows how to spell latin character words or acronyms in Japanese. For example NHK is spelled enuetchikē.

• A エー ē (or エイ ei)
• B ビー bī
• C シー shī
• D ディー dī
• E イー ī
• F エフ efu
• G ジー jī
• H エッチ etchi/ecchi (or エイチ eichi)
• I アイ ai
• J ジェー jē (or ジェイ jei)
• K ケー kē (or ケイ kei)
• L エル eru
• M エム emu
• N エヌ enu
• O オー ō
• P ピー pī
• Q キュー kyū
• R アール āru
• S エス esu
• T ティー tī (or チー chī)
• U ユー yū
• V ヴイ vui; (or ブイ bui)
• W ダブリュー daburyū
• X エックス ekkusu
• Y ワイ wai
• Z ゼット zetto