The Maryland House gave preliminary approval today to a bill that would provide an estimated 70,000 state employes with a form of collective bargaining but would prohibit binding arbitration and strikes.

The state's labor unions are sharply divided over whether the measure would give them any real bargaining power. Today's voice vote by the House is the furthest any collective bargaining legislation has gotten in the assembly. Similar bills have died in committee in the past, and even this watered-down measure is expected to face strong opposition in the Senate.

Support in the House, however, was sufficient to fight off several amendments that would have exempted Maryland state troopers, university professors and firefighters from the bill. Sponsors of the amendments argued that these groups did not want collective bargaining.

The bill would require that agreements be submitted to the governor and the assembly for approval. But the governor would not be required to put money in the budget once wage increases had been agreed upon. The bill would not allow for binding arbitration in the event of an impasse during negotiations. Instead, fact-finders would be allowed to review the positions of both sides and issue an advisory recommendation.

Strikes would be prohibited, and any union or bargaining representative that called for or sanctioned a strike would be decertified.

Del. Helen L. Koss (D-Montgomery), chairman of the House Constitutional and Administrative Law Committee defended the measure as giving the right to collective bargaining to state employes, but not forcing it on them. Koss, whose committee sent the bill to the House floor, said it would take the support of 30 percent of any unit before a bargaining representative election could be held. Even then, she said, the employes could still vote against having collective bargaining representation.