Pitch plays a significant role in understanding a tone based language like Mandarin. In this paper, we present a new method that estimates F0 contour for electrolaryngeal (EL) speech enhancement in Mandarin. Our system explores the usage of phonetic feature to improve the quality of EL speech. First, we train an acoustic model for EL speech and generate the phoneme posterior probabilities feature sequence for each input EL speech utterance. Then we employ the phonetic feature for F0 contour generation rather than the acoustic feature. The experimental results indicate that the EL speech is significantly enhanced under the adoption of the phonetic feature. Experimental results demonstrate that the proposed method achieves notable improvement regarding the intelligibility and the similarity with normal speech.