This study aimed to identify the degree of cognitive training needs of the respondents supervisors working in the maintenance of public parks in Riyadh, according to their self-assessment. The study was conducted on 130 supervisor representing 38% of the overall population of all the supervisors working on the seven sites of the city of Riyadh.  Preliminary data were collected through personal interviews using a questionnaire. Data collected were subjected to statistical analysis and presented in the form of: the percentages, arithmetic means, standard deviation, the simple Spearman correlation coefficient, and multiple regression analysis (Stepwise). Findings of the study revealed that training needs for some 74% of the respondents were low, and 83.1% of respondents were applying their skills and knowledge at a high level. The results of the study also showed a significant negative correlation between the degree of the training requirement (dependent variable) and the independent variables like: scientific specialization and the level of education at the probability level of (0.01). Also a positive relationship for the nationality of the respondents was found at the same probability level of (0.01).  However, significant negative relationships were realized for the independent variables like: place of duty, experience in years, and the information sources at the probability level (0.05). The study exhibited a positive relationship at the same level with the probability for the variables like: place of birth, and the monthly salary. While no significant relationship has not been established at any of the levels for any of the independent variables like: age, marital status, training. The respondents identified the most important obstacles making their work performance low and offered 13 suggestions to improve their working. Some 30.8% of the respondents suggest that training programs are needed to increase the working of the supervisors and employees.  Whereas about 15.4% of them emphasize the need to adhere to the implementation of programs chalked out for the maintenance work and assignments mentioned.   About 13.8% of the respondents felt the need for the provision of appropriate machinery, equipment and spare parts to undertake their activities better. As little as 1.5% of the total respondents suggested to prepare a comprehensive study to take advantage of the resulting crop of dates of gardens, whether they are good for human consumption or better to convert them to feed.  The purpose of the study was to raise the efficiency of the workers/field supervisors involved in the maintenance of public gardens.