Objectives of this researchis to know the effect of the exposure of telephone celluler wave toward fertility in mice (Mus musculus) by measuring the diameter of tubulus seminiferi and counting the percentage of spermatogenic cells. This research use mice (Mus musculus) strain Balb-C, 3 months age, ± 30 gram body weight. This mice divided into 4 groups, they are K (control), P1 (exposure of telephone celluler wave type GSM monophonic), P2 (exposure of telephone celluler wave type GSM polyphonic), P3 (exposure of telephone celluler wave type CDMA). These mice were given exposure of telephone celluler wave by placing them near telephone celluler which active telephone condition. Duration of the exposure is ± 120 minutes in a days. These mice were sacrificed by decapitation, its testes were taken and make the histological preparation. Microscopic observation was done by measuring the diameter of tubulus seminiferi and counting the percentage of spermatogenic cells, such as spermatogonium, spermatocyt, and spermatidium. The results was analyzed by one way Anova continued by Tukey test. Results of this research showed that comparing with the control group, the measurement of diameter tubulus seminiferi and the number of spermatogenic cells especially spermatidium in treatment groups were decreasing. It can conclude that telephone celluler wave can cause the decreasing offertility by inhibiting the spermatogenesis process.Tujuan penelitian ini adalah untuk mengetahui pengaruh pajanan gelombang telepon seluler terhadap fertilitas mencit (Mus musculus) dengan mengukur diameter tubulus seminiferi dan menghitung prosentase sel-sel spermatogenik. Desain penelitian adalah eksperimental in vivo pada hewan uji. Penelitian ini menggunakan sampel berupa mencit (Mus musculus) jantan galur Balb-C 20 ekor, berumur 3 bulan, dan berat badan ± 30 gram. Mencit dibagi menjadi 4 kelompok, yaitu kelompok K (kontrol), P1(terpajan gelombang telepon seluler jenis GSM monophonic), P2(terpajan gelombang telepon seluler jenis GSM polyphonic), dan P3(terpajan gelombang telepon seluler jenis CDMA). Hewan uji tersebut diberi pajanan gelombang telepon seluler dengan cara meletakkan hewan uji di dekat telepon seluler yang sedang aktif menelpon. Lama pemajanan ± 120 menit perhari selama 30 hari. Pembedahan hewan uji dilakukan untuk mengambil testisnya dan kemudian dibuat preparat. Pengamatan preparat dilakukan dengan mengukur diameter tubulus seminiferi dan menghitung prosentase sel-sel spermatogenik, antara lain spermatogonium, spermatocyt, dan spermatidium. Hasil dianalisis dengan metode Anova 1 jalan kemudian dilanjutkan dengan uji Tukey. Hasil penelitian menunjukkan bahwa ukuran diameter tubulus seminiferi danjumlah prosentase sel-sel spermatogenik khususnya spermatidium pada kelompok perlakuan mengalami penurunan dibandingkankelompok kontrol. Jadi dapat disimpulkan bahwa gelombang telepon seluler dapat meyebabkan terjadinya penurunan tingkat ferilitas dengan cara mengganggu proses spermatogenesis.