The objective of this paper is to examine the role of leadership functions in personnel motivation in security organizations. To this end, the paper also identified some of the challenges and solutions to such challenges insecurity organizations with particular emphasis on the Nigeria Police. Hierarchy of needs theory and contingency management model were adopted in explaining the relevance of effective leadership function in increasing the motivation of personnel insecurity organizations. Using secondary data, the paper established that most of the challenges of the Nigeria Police, such as lack of professionalism and competency, corruption, ethnicity, and extrajudicial treatment of the civilians are attributable to ineffective leadership within the organization and the bad political leadership at the national level. The paper concluded that without effective leadership function, no security agency can function well in Nigeria. As the solutions to the challenges of ineffective leadership function in the Nigerian security organizations, the paper suggested that: rule of law should been forced on all Nigerians including the Police and other security personnel; management section of the security agencies should ensure proper checkmating between the different divisions; police corruption must be fought by frequently monitoring the activities of the organization; the reward package (salary) of the Nigerian Police and other security agencies should be reviewed, etc.