Adding to @gaeguri's answer, the word '창조' seems to have a different meaning in North Korean as the linked Naver North Korean dictionary indicates:
[북한어 (North Korean)] 주의, 사상, 학설 따위를 처음으로 만들어 낸 사람. A person who invented (made, created) a principle (ideology/idea or belief), philosophy or theory.
Its Chinese characters are '創祖' and you should note that '祖' here means (1) grandfather, (2) ancestor and (3) beginning or start, etc. '祖' is different from '造' which is used in South Korean meaning to build or create.
Therefore, the phrase could be translated to
Knowledge is the greatest asset for inventor (creator) of communist theory and building of communist society.
Even if '창조' has the same meaning as South Korean, i.e., 'creation', it could be translated to
Knowledge is the greatest asset for creation and building of communist society.
Their catchphrase or slogans are generally politically motivated and they are almost always about praising their leaders and ideology. It seems obvious what they want to create and build.
A side note: As you mentioned, the phrase is related with the North Korean political ideology, i.e., 주체사상 (Juche Idea or Self-reliance Idea). As a non-expert of North Korean, the above is the best I could possibly translate.