Detection of identity, quantity and viability of cells at the point-of-need is critically needed for diagnostic, surveillance and monitoring purposes. In this work, we present a broadband electrical sensor combined with a microfluidic device to detect mammalian cells and bacteria. It is found that the device can detect down to single mammalian cells in a suspension. The device is also capable of differentiating cells based on their viability and size. With a specific cell type, cell number can be obtained through signal analysis. Compared to conventional impedance sensors that operate in narrow and low frequency ranges, this device not only detects the properties of cell membranes in the MHz range, but also the intracellular environment in the GHz range, thus revealing richer information about the cell identity and function. Ongoing research intends to optimize the sensor performance to extract biochemical signature from cells.