A cell analyzer comprising - a detecting section configured to detect optical information of each cell from a measurement specimen containing cells harvested from an epithelial tissue, and - a controller programmed to acquire feature parameters of each cell based on the detected optical information, wherein said feature parameters include a first parameter related to the size of the cell and a second parameter related to the size of a cell nucleus, and to determine appropriateness of the cell harvesting of parabasal cells based on said feature parameters (N, C), characterized in that - said controller is further configured to acquire: - the number of cells having a ratio (N/C) of a second parameter to a first parameter comprised between a first threshold and a second threshold selected so that said number of cells represents the number of parabasal cells; - the number of cells having a ratio (N/C) of a second parameter to a first parameter lower than said first threshold selected so that said number of cells represent the number of intermediate and surface cells; - the appropriateness of the cell harvesting of parabasal cells based on said feature parameters (N, C) is determined by: - comparing the ratio (N1/N2) of the acquired number of parabasal cells to the acquired number of intermediate and surface cells to a first appropriateness threshold; and in addition - comparing the acquired number of parabasal cells with a second appropriateness threshold and/or comparing the acquired number of intermediate and surface cells to a third appropriateness threshold. - a detecting section configured to detect optical information of each cell from a measurement specimen containing cells harvested from an epithelial tissue, and - a controller programmed to acquire feature parameters of each cell based on the detected optical information, wherein said feature parameters include a first parameter related to the size of the cell and a second parameter related to the size of a cell nucleus, and to determine appropriateness of the cell harvesting of parabasal cells based on said feature parameters (N, C), characterized in that - said controller is further configured to acquire: - the number of cells having a ratio (N/C) of a second parameter to a first parameter comprised between a first threshold and a second threshold selected so that said number of cells represents the number of parabasal cells; - the number of cells having a ratio (N/C) of a second parameter to a first parameter lower than said first threshold selected so that said number of cells represent the number of intermediate and surface cells; - said controller is further configured to acquire: - the number of cells having a ratio (N/C) of a second parameter to a first parameter comprised between a first threshold and a second threshold selected so that said number of cells represents the number of parabasal cells; - the number of cells having a ratio (N/C) of a second parameter to a first parameter lower than said first threshold selected so that said number of cells represent the number of intermediate and surface cells; - the number of cells having a ratio (N/C) of a second parameter to a first parameter comprised between a first threshold and a second threshold selected so that said number of cells represents the number of parabasal cells; - the number of cells having a ratio (N/C) of a second parameter to a first parameter lower than said first threshold selected so that said number of cells represent the number of intermediate and surface cells; - the appropriateness of the cell harvesting of parabasal cells based on said feature parameters (N, C) is determined by: - comparing the ratio (N1/N2) of the acquired number of parabasal cells to the acquired number of intermediate and surface cells to a first appropriateness threshold; and in addition - comparing the acquired number of parabasal cells with a second appropriateness threshold and/or comparing the acquired number of intermediate and surface cells to a third appropriateness threshold. - comparing the ratio (N1/N2) of the acquired number of parabasal cells to the acquired number of intermediate and surface cells to a first appropriateness threshold; and in addition - comparing the acquired number of parabasal cells with a second appropriateness threshold and/or comparing the acquired number of intermediate and surface cells to a third appropriateness threshold.