He authored many works while leading the party for half a century.

Among the works published by him in the 1960s are "Broadcasting Is an Important Political Medium" and "Film Artistes Are Standard-Bearers on the Ideological Front of Our Party".

In those works, he clarified an idea of strengthening the single-minded unity of the revolutionary ranks around the leader.

Among his works are also "On Some Immediate Tasks for Ideological Work of the Party to Model the Whole Society on Kimilsungism" and "On the Fundamentals of Revolutionary Party Building."

In those works he set forth the tasks and ways to develop the Workers' Party of Korea into the eternal party of President Kim Il Sung, model the whole society on the idea of the leader in order to carry forward the revolutionary cause of Juche generation after generation.

Kim Jong Il gave scientific answers to the theoretical and practical issues arising in achieving the unity of the revolutionary ranks in some of his works.

Among them are "On the Juche Idea" and "On Some Problems of Education in the Juche Idea".

He in his works put forward the idea of building the People's Army into the army of the leader and the party.

Among those works are "The People's Army Should Devotedly Safeguard Its Leader, Party, Social System and Country" and "Let Us Strengthen the People's Army into Invincible Ranks".

He also authored works calling for further strengthening the unity and cohesion of the Party and people in conformity with the intrinsic requirements of socialist society and as required by the developing revolution and underscoring the need to give full play to the popular masses' creative ingenuity and combining the work for the unity of the collective with various mass movements.

He published in the new century such works as "The Revolutionary Comradeship Is the Foundation of the Single-minded Unity and an Engine of Our Revolution" and "The Democratic People's Republic of Korea Is a Socialist State of Juche with Invincible Might".

In those works he encouraged the whole party and all people in the struggle for building a thriving nation.