"humble leader" is correct and usable in written English.
You can use it when referring to a leader who is not boastful and is humble in their approach. For example, "The CEO is a modest and humble leader who has brought great success to the company."
But the posters are not being removed quietly in the night by a humble leader.
Eventually, Roginsky became its chairman and most effective, if humble, leader.
Abbado is a peculiarly humble leader who has failed to cultivate a Karajanesque mystique in the press.
Holding his cowboy hat in hand, he prayed, "Father, we plead with you that you would give us a godly, humble leader of the Texas House".
She is a conscientious, hardworking and humble leader and this shows in her commitment to giving staff the best possible working experience.
Kaepernick, with his tattoos and his ostentatious touchdown celebrations has been portrayed as arrogant and self-centred, while Wilson is presented as the quiet and humble leader.
In general, the corporate world needs its flamboyant visionaries and raging egomaniacs rather more than its humble leaders and corporate civil servants.
In recent decades the Conservatives have been as attuned to these nuances as anyone, preferring humble leaders to pukka ones; as far back as 1923 they picked Stanley Baldwin above Lord Curzon ("a most superior person"), partly for that reason.
We need humble leaders, because humility is the cornerstone of moral authority.
Humble leaders make space for others to be better, more engaged, powerful, and accountable.
Humble leaders contract, make themselves small, and give others the chance to rise to the occasion.
